Tüm alıştırma soruları

2131 soru

Soru 2021Soru

On a number line, point AA is located at 1010 and point BB is located at 22. If point PP, with coordinate x>0x > 0, is three times as far from point AA as it is from point BB, what is the value of xx?

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Cevap: 4

Cevap

4
The distance from P(x)P(x) to A(10)A(10) is x10|x - 10| and to B(2)B(2) is x2|x - 2|. Setting x10=3x2|x - 10| = 3|x - 2| gives two equations: x10=3x6x - 10 = 3x - 6, which yields x=2x = -2, and x10=3x+6x - 10 = -3x + 6, which yields x=4x = 4. Since x>0x > 0, the correct value is 4.

Adım Adım Çözüm

1
Formulate the distance relationship using absolute value notation.
x10=3x2|x - 10| = 3|x - 2|
The distance between two points uu and vv on the real number line is given by uv|u - v|.
2
Split the absolute value equation into two linear equations representing possible cases.
x10=3(x2)x - 10 = 3(x - 2) or x10=3(x2)x - 10 = -3(x - 2)
The equality a=b|a| = |b| implies a=ba = b or a=ba = -b.
3
Solve each case algebraically.
Case 1 gives x10=3x6    2x=4    x=2x - 10 = 3x - 6 \implies 2x = -4 \implies x = -2. Case 2 gives x10=3x+6    4x=16    x=4x - 10 = -3x + 6 \implies 4x = 16 \implies x = 4.
Standard linear equation solving.
4
Apply the given domain condition x>0x > 0.
x=4x = 4
The solution x=2x = -2 is negative and therefore violates the condition x>0x > 0.

Anahtar Kavram

Distance on a number line represented by absolute value equations
Soru 2022Soru

A research laboratory conducted 66 experimental trials to measure the duration, in milliseconds, of a specific chemical reaction. The durations recorded for 55 of the trials were 240240, 215215, 260260, 225225, and 245245. If the median duration of all 66 trials was 235235 milliseconds, what was the duration, in milliseconds, of the 6th trial?

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Cevap: 230

Cevap

230
For a dataset with 6 numbers, the median is the arithmetic mean of the 3rd and 4th numbers in ascending order. Arranging the 5 given numbers gives 215,225,240,245,260215, 225, 240, 245, 260. Since the target median is 235235, the sum of the two middle numbers must be 235×2=470235 \times 2 = 470. Placing x=230x = 230 into the dataset yields the ordered set 215,225,230,240,245,260215, 225, 230, 240, 245, 260, where the 3rd and 4th numbers are 230230 and 240240. Their mean is (230+240)/2=235(230 + 240) / 2 = 235, which matches the given median.

Adım Adım Çözüm

1
Order the 5 given numbers from least to greatest
The sorted list of known values is 215,225,240,245,260215, 225, 240, 245, 260.
Calculating or using median requires ordering the data points.
2
Express the median condition for an even number of data points (n=6n = 6)
Median=3rd value+4th value2=235\text{Median} = \frac{\text{3rd value} + \text{4th value}}{2} = 235, so 3rd value+4th value=470\text{3rd value} + \text{4th value} = 470.
For an even number of values, the median is the average of the two middle numbers.
3
Determine the position and value of the unknown 6th trial xx
If x225x \le 225, the 3rd and 4th values would be 225225 and 240240 (median 232.5232.5). If x245x \ge 245, the 3rd and 4th values would be 240240 and 245245 (median 242.5242.5). Thus, xx must lie between 225225 and 240240.
Analyzing boundary conditions places xx as the 3rd value and 240240 as the 4th value.
4
Solve for xx
x+240=470    x=230x + 240 = 470 \implies x = 230.
The sum of the two middle values must equal 470470 to yield a median of 235235.

Anahtar Kavram

Finding a missing value in a dataset given the median of an even number of observations.
Soru 2023Soru

A reliability engineering test evaluates two independent components, Component X and Component Y, in a machine. The probability that Component X fails during operation is 0.200.20, and the probability that Component Y fails during operation is 0.300.30. What is the probability that at least one of the two components operates successfully during operation?

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Cevap: 0.940.94

Cevap

The probability that at least one of the two components operates successfully is 0.940.94.
The correct answer is 0.940.94. The complement of the event 'at least one component operates successfully' is the event 'both components fail'. Because Component X and Component Y fail independently, P(both fail)=P(X fails)×P(Y fails)=0.20×0.30=0.06P(\text{both fail}) = P(\text{X fails}) \times P(\text{Y fails}) = 0.20 \times 0.30 = 0.06. Subtracting this complementary probability from 11 yields 10.06=0.941 - 0.06 = 0.94.

Adım Adım Çözüm

1
Determine the probability that each component fails.
P(X fails)=0.20P(\text{X fails}) = 0.20 and P(Y fails)=0.30P(\text{Y fails}) = 0.30.
These probabilities are explicitly given in the problem statement.
2
Calculate the joint probability that BOTH components fail simultaneously using the multiplication rule for independent events.
P(both fail)=P(X fails)×P(Y fails)=0.20×0.30=0.06P(\text{both fail}) = P(\text{X fails}) \times P(\text{Y fails}) = 0.20 \times 0.30 = 0.06.
Since the components fail independently, their joint failure probability is the product of their individual failure probabilities.
3
Apply the complement rule to find the probability that at least one component operates successfully.
P(at least one succeeds)=1P(both fail)=10.06=0.94P(\text{at least one succeeds}) = 1 - P(\text{both fail}) = 1 - 0.06 = 0.94.
The event 'at least one component succeeds' is the exact complement of 'both components fail'.

Anahtar Kavram

Independent Events and Complement Probability Rule
Soru 2024Soru

A commercial coffee roasting facility operates three roasters: XX, YY, and ZZ.

- Roaster XX processes coffee beans at a constant rate of 60 kg/hr60\text{ kg/hr}, producing a blend with an Arabica-to-Robusta ratio of 3:23:2 by weight.
- Roaster YY processes coffee beans at a constant rate of 90 kg/hr90\text{ kg/hr}, producing a blend with an Arabica-to-Robusta ratio of 2:12:1 by weight.
- Roaster ZZ processes coffee beans at a constant rate of 150 kg/hr150\text{ kg/hr}, producing a blend with an Arabica-to-Robusta ratio of 1:41:4 by weight.

All three roasters operate simultaneously for 44 hours to complete a production order. Which of the following statements regarding the production output over this 44-hour period must be true? Select all such statements.

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Cevap: The total weight of Arabica beans processed across all three roasters is 504 kg504\text{ kg}.; Arabica beans account for exactly 42%42\% of the total weight of coffee beans processed.; The overall ratio of total Arabica weight to total Robusta weight produced is 21:2921:29.

Cevap

The statements confirming that total Arabica weight is 504 kg504\text{ kg}, Arabica accounts for 42%42\% of total weight, and the overall ratio of Arabica to Robusta is 21:2921:29 are all correct.
The total production from Roaster XX is 240 kg240\text{ kg} (144 kg144\text{ kg} Arabica, 96 kg96\text{ kg} Robusta), from Roaster YY is 360 kg360\text{ kg} (240 kg240\text{ kg} Arabica, 120 kg120\text{ kg} Robusta), and from Roaster ZZ is 600 kg600\text{ kg} (120 kg120\text{ kg} Arabica, 480 kg480\text{ kg} Robusta). The total Arabica weight is 144+240+120=504 kg144 + 240 + 120 = 504\text{ kg}, which constitutes 5041,200=42%\frac{504}{1,200} = 42\% of the 1,200 kg1,200\text{ kg} total output. The remaining 696 kg696\text{ kg} is Robusta, giving an Arabica to Robusta ratio of 504:696=21:29504:696 = 21:29.

Adım Adım Çözüm

1
Calculate total output and Arabica quantity for each roaster over 4 hours
Roaster XX: 240 kg240\text{ kg} total, 35×240=144 kg\frac{3}{5} \times 240 = 144\text{ kg} Arabica. Roaster YY: 360 kg360\text{ kg} total, 23×360=240 kg\frac{2}{3} \times 360 = 240\text{ kg} Arabica. Roaster ZZ: 600 kg600\text{ kg} total, 15×600=120 kg\frac{1}{5} \times 600 = 120\text{ kg} Arabica.
Converting hourly rates to total batch weights over 44 hours and applying part-to-whole fractions determined by each ratio.
2
Aggregate total Arabica and Robusta weights across all roasters
Total Arabica = 144+240+120=504 kg144 + 240 + 120 = 504\text{ kg}. Total coffee = 240+360+600=1,200 kg240 + 360 + 600 = 1,200\text{ kg}. Total Robusta = 1,200504=696 kg1,200 - 504 = 696\text{ kg}.
Adding individual component weights to get total aggregate weights.
3
Evaluate percentage and ratio statements
Arabica percentage = 5041,200×100%=42%\frac{504}{1,200} \times 100\% = 42\%. Arabica to Robusta ratio = 504696=2129\frac{504}{696} = \frac{21}{29}.
Verifying overall proportions and simplifying the fraction by dividing by 2424.

Anahtar Kavram

Multi-stage weighted component ratios and rate conversion
Soru 2025Soru

In his reevaluation of early twentieth-century monetary policy, economist Arthur Pendelton argues that central bankers during the Interwar period were not merely conservative functionaries adhering to outdated doctrine; rather, they were 'trimming their sails to the prevailing trade winds' of domestic political pressure while publicly professing an unyielding commitment to the gold standard. Far from operating as disinterested technocrats governed strictly by abstract theory, these policy makers constantly calibrated their interest rate adjustments to appease vocal domestic electoral blocs. Consequently, their public declarations of monetary orthodoxy functioned less as an operational blueprint than as an ideological veil, masking a series of opportunistic compromises that ultimately undermined international financial stability.

Based on the passage, the figurative expression 'trimming their sails to the prevailing trade winds' serves to convey which of the following regarding the central bankers? Select all that apply.

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Cevap: Adapting strategic policy choices to accommodate external political forces; Maintaining a pragmatically flexible posture despite public assertions of unyielding principle

Cevap

The correct selections are the options stating that the central bankers adapted strategic policy choices to accommodate external political forces and that they maintained a pragmatically flexible posture despite public assertions of unyielding principle.
The phrase 'trimming their sails to the prevailing trade winds' uses nautical imagery to describe adjusting one's actions to accommodate shifting external forces. In context, the author uses this expression to show that central bankers calibrated interest rates in response to domestic political pressure while maintaining a public façade of adherence to the gold standard. Thus, the selections indicating political adaptation and pragmatic flexibility behind a rigid public stance correctly interpret the metaphor's contextual meaning.

Adım Adım Çözüm

1
Analyze the figurative expression within its immediate sentence context.
The phrase 'trimming their sails to the prevailing trade winds' is contrasted with 'publicly professing an unyielding commitment' and directly linked to responding to 'domestic political pressure'.
Understanding how the metaphor operates rhetorically requires identifying the contrast signals and defining context clues.
2
Determine the metaphorical meaning of the phrase.
'Trimming sails' means adjusting nautical sails to handle wind direction, metaphorically indicating modifying behavior or policy to suit changing political conditions.
Idioms in academic text translate physical or functional analogies into abstract behavioral descriptions.
3
Evaluate the option choices against the derived contextual meaning.
Options reflecting political adaptation and flexible pragmatism beneath an unyielding façade accurately capture the dual implications of the metaphor.
Multiple-choice select-all questions require identifying all valid contextual nuances while eliminating literal, extreme, or out-of-scope distractors.

Anahtar Kavram

Interpreting Idiomatic Usage and Figurative Language in Context
Soru 2026Soru

If aa and bb are nonzero real numbers such that a2b3<0a^2 b^3 < 0 and a2b4=ab2\sqrt{a^2 b^4} = -a b^2, which of the following statements must be true? Select all such statements.

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Cevap: a+b<0a + b < 0; a3b>0\frac{a^3}{b} > 0

Cevap

The statements that must be true are the inequality asserting that the sum of the variables is negative (a+b<0a + b < 0) and the inequality asserting that the quotient of the cubed variable and the second variable is positive (a3b>0\frac{a^3}{b} > 0).
Analyzing the given constraints reveals that both variables are negative. From a2b3<0a^2 b^3 < 0, since a2>0a^2 > 0, we must have b3<0b^3 < 0, so b<0b < 0. Next, from a2b4=ab2=ab2\sqrt{a^2 b^4} = |a| b^2 = -a b^2, dividing by b2>0b^2 > 0 gives a=a|a| = -a, which implies a<0a < 0. Thus, a<0a < 0 and b<0b < 0. The statement asserting a+b<0a + b < 0 is true because the sum of two negative numbers is negative. The statement asserting a3b>0\frac{a^3}{b} > 0 is true because a3<0a^3 < 0 and b<0b < 0, and dividing two negative numbers yields a positive quotient.

Adım Adım Çözüm

1
Determine the sign of bb using the given inequality a2b3<0a^2 b^3 < 0.
b<0b < 0
Since aa is a nonzero real number, a2>0a^2 > 0. For the product a2b3a^2 b^3 to be negative, b3b^3 must be negative, which implies b<0b < 0.
2
Determine the sign of aa using the identity a2b4=ab2\sqrt{a^2 b^4} = -a b^2.
a<0a < 0
Simplify the radical: a2b4=a2(b2)2=ab2\sqrt{a^2 b^4} = \sqrt{a^2} \cdot \sqrt{(b^2)^2} = |a| b^2. Equating this to ab2-a b^2 gives ab2=ab2|a| b^2 = -a b^2. Since b0b \neq 0, b2>0b^2 > 0, so dividing by b2b^2 yields a=a|a| = -a. For a nonzero real number, a=a|a| = -a implies a<0a < 0.
3
Evaluate statement a+b<0a + b < 0.
True
The sum of two negative numbers (a<0a < 0 and b<0b < 0) is always negative.
4
Evaluate statement a3b>0\frac{a^3}{b} > 0.
True
Since a<0a < 0, a3<0a^3 < 0. Dividing the negative quantity a3a^3 by the negative quantity bb yields a positive result.
5
Evaluate statement a4b2=a2b\sqrt{a^4 b^2} = a^2 b.
False
a4b2=a4b2=a2b\sqrt{a^4 b^2} = \sqrt{a^4}\sqrt{b^2} = a^2 |b|. Since b<0b < 0, b=b|b| = -b, so a4b2=a2b\sqrt{a^4 b^2} = -a^2 b.
6
Evaluate statement (a)3b2<0(-a)^3 b^2 < 0.
False
Since a<0a < 0, a>0-a > 0, making (a)3>0(-a)^3 > 0. Since b0b \neq 0, b2>0b^2 > 0. The product of two positive numbers is positive, so (a)3b2>0(-a)^3 b^2 > 0.
7
Evaluate statement (a+b)2=a+b\sqrt{(a + b)^2} = a + b.
False
x2=x\sqrt{x^2} = |x| for any real xx. Since a+b<0a + b < 0, (a+b)2=a+b=(a+b)a+b\sqrt{(a + b)^2} = |a + b| = -(a + b) \neq a + b.

Anahtar Kavram

Properties of even exponents, odd exponents, and principal square roots of negative variable terms.
Soru 2027Soru

A manufacturing plant operates two assembly lines, Line X and Line Y. Line X produces 15 units per hour, and Line Y produces 22 units per hour. On a certain day, Line X operated for 3 hours longer than Line Y did, and the two lines produced a total of 415 units. How many hours did Line Y operate?

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Cevap: 10

Cevap

10
Let hh represent the number of hours Line Y operated. Because Line X operated for 3 hours longer than Line Y, Line X operated for h+3h + 3 hours. The total number of units produced by both lines is the sum of their individual outputs: 15(h+3)+22h=41515(h + 3) + 22h = 415. Distributing 15 yields 15h+45+22h=41515h + 45 + 22h = 415. Combining like terms gives 37h+45=41537h + 45 = 415. Subtracting 45 from both sides yields 37h=37037h = 370, and dividing by 37 gives h=10h = 10. Therefore, Line Y operated for 10 hours.

Adım Adım Çözüm

1
Define the variable representing Line Y's operating time in hours.
Let hh represent the number of hours Line Y operated. Line X's operating time is h+3h + 3 hours.
Line X operated for 3 hours longer than Line Y.
2
Formulate a linear equation in one variable for total units produced.
15(h+3)+22h=41515(h + 3) + 22h = 415
Total production is the sum of production from Line X (15×(h+3)15 \times (h + 3)) and Line Y (22×h22 \times h).
3
Distribute and combine like terms on the left side of the equation.
15h+45+22h=415    37h+45=41515h + 45 + 22h = 415 \implies 37h + 45 = 415
Apply the distributive property and combine variable terms.
4
Isolate the variable hh.
37h=370    h=1037h = 370 \implies h = 10
Subtract 45 from both sides of the equation and divide by 37.

Anahtar Kavram

Linear Equations in One Variable
Tahmini Süre:1m 30s
Soru 2028Soru

A convex hexagon has five interior angles measuring 115115^\circ, 125125^\circ, 130130^\circ, 140140^\circ, and 150150^\circ. What is the measure, in degrees, of the exterior angle adjacent to the sixth interior angle?

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Cevap: 120120^\circ

Cevap

The measure of the exterior angle adjacent to the sixth interior angle is 120120^\circ.
The sum of the interior angles of a 6-sided polygon (hexagon) is given by (62)×180=720(6 - 2) \times 180^\circ = 720^\circ. The sum of the five given interior angles is 115+125+130+140+150=660115^\circ + 125^\circ + 130^\circ + 140^\circ + 150^\circ = 660^\circ, which leaves 720660=60720^\circ - 660^\circ = 60^\circ for the sixth interior angle. Since an interior angle and its adjacent exterior angle are supplementary, the exterior angle is 18060=120180^\circ - 60^\circ = 120^\circ.

Adım Adım Çözüm

1
Calculate the sum of the interior angles for a convex hexagon.
Using (n2)×180(n - 2) \times 180^\circ with n=6n = 6, the total interior angle sum is (62)×180=4×180=720(6 - 2) \times 180^\circ = 4 \times 180^\circ = 720^\circ.
The sum of interior angles of any convex polygon with nn sides is (n2)×180(n - 2) \times 180^\circ.
2
Find the sum of the five given interior angles.
115+125+130+140+150=660115^\circ + 125^\circ + 130^\circ + 140^\circ + 150^\circ = 660^\circ.
Summing the five known angle values is necessary to find the remaining sixth angle.
3
Determine the measure of the sixth interior angle.
720660=60720^\circ - 660^\circ = 60^\circ.
Subtracting the sum of the five interior angles from the total interior angle sum yields the sixth interior angle.
4
Calculate the supplementary exterior angle.
18060=120180^\circ - 60^\circ = 120^\circ.
An interior angle and its adjacent exterior angle form a straight line and are supplementary (180180^\circ).

Anahtar Kavram

Interior and Exterior Angles of Convex Polygons
Soru 2029Soru

The prime factorizations of two positive integers AA and BB are given by A=2a×35×5bA = 2^a \times 3^5 \times 5^b and B=24×3c×72B = 2^4 \times 3^c \times 7^2, where aa, bb, and cc are positive integers. If the greatest common divisor of AA and BB is gcd(A,B)=22×33\gcd(A, B) = 2^2 \times 3^3, and their least common multiple is \text{lcm}(A,B)=24×35×53×72(A, B) = 2^4 \times 3^5 \times 5^3 \times 7^2, what is the value of a+b+ca + b + c?

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Cevap: 8

Cevap

The correct answer is 8.
For any two positive integers expressed in prime factorized form, the greatest common divisor contains each prime factor raised to the minimum of its exponents in the two numbers, while the least common multiple contains each prime factor raised to the maximum of its exponents. For prime factor 2, the GCD has exponent 2, so min(a, 4) = 2, giving a = 2. For prime factor 3, the GCD has exponent 3, so min(5, c) = 3, giving c = 3. For prime factor 5, the LCM has exponent 3, so max(b, 0) = 3, giving b = 3. Adding these values together yields a + b + c = 2 + 3 + 3 = 8.

Adım Adım Çözüm

1
Analyze the prime factor 22
min(a, 4) = 2, so a = 2
The greatest common divisor takes the minimum exponent for each prime factor shared between A and B.
2
Analyze the prime factor 33
min(5, c) = 3, so c = 3
The exponent of 3 in the GCD is 3, which must equal the smaller of the two exponents 5 and c.
3
Analyze the prime factor 55
max(b, 0) = 3, so b = 3
The least common multiple takes the maximum exponent for each prime factor present in either number.
4
Calculate the sum a+b+ca + b + c
2 + 3 + 3 = 8
Add the solved values of the three unknown prime exponents.

Anahtar Kavram

Relating prime factor exponents to GCD (minimum exponent) and LCM (maximum exponent)
Soru 2030Soru
If xx is a positive integer such that
4x+4x+4x+4x2x+2x=512\frac{4^x + 4^x + 4^x + 4^x}{2^x + 2^x} = 512
what is the value of xx?
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Cevap: 8

Cevap

The value of xx is 8.
Combining four terms of 4x4^x yields 44x=4x+1=22x+24 \cdot 4^x = 4^{x+1} = 2^{2x+2}. Combining two terms of 2x2^x yields 22x=2x+12 \cdot 2^x = 2^{x+1}. Dividing the numerator by the denominator gives 22x+2(x+1)=2x+12^{2x+2 - (x+1)} = 2^{x+1}. Since 512=29512 = 2^9, setting 2x+1=292^{x+1} = 2^9 gives x+1=9x + 1 = 9, which leads directly to x=8x = 8.

Adım Adım Çözüm

1
Simplify the numerator by combining identical added terms.
The numerator 4x+4x+4x+4x4^x + 4^x + 4^x + 4^x equals 44x4 \cdot 4^x, which simplifies to 4x+14^{x+1}.
Adding four identical quantities is equivalent to multiplying that quantity by 4.
2
Simplify the denominator by combining identical added terms.
The denominator 2x+2x2^x + 2^x equals 22x2 \cdot 2^x, which simplifies to 2x+12^{x+1}.
Adding two identical quantities is equivalent to multiplying that quantity by 2.
3
Convert the numerator to base 2 and simplify the fraction.
Since 4x+1=(22)x+1=22x+24^{x+1} = (2^2)^{x+1} = 2^{2x+2}, the fraction becomes 22x+22x+1=2(2x+2)(x+1)=2x+1\frac{2^{2x+2}}{2^{x+1}} = 2^{(2x+2)-(x+1)} = 2^{x+1}.
Converting all terms to a common base allows using the exponent quotient rule am/an=amna^m / a^n = a^{m-n}.
4
Solve for xx by equating the simplified power to 512.
Setting 2x+1=512=292^{x+1} = 512 = 2^9 yields x+1=9x + 1 = 9, so x=8x = 8.
When exponential expressions with the same positive base (other than 1) are equal, their exponents must be equal.

Anahtar Kavram

Combining repeated addition of exponential terms and converting powers to a common base using exponent laws (aman=am+na^m \cdot a^n = a^{m+n} and aman=amn\frac{a^m}{a^n} = a^{m-n}).
Soru 2031Soru

Given non-zero real numbers xx and yy where xy|x| \neq |y|, simplify the complex rational expression:

x3+y3x2y2x2yxy2(xy)2x4y4x3+x2y+xy2+y3\frac{\frac{x^3 + y^3}{x^2 - y^2} - \frac{x^2y - xy^2}{(x - y)^2}}{\frac{x^4 - y^4}{x^3 + x^2y + xy^2 + y^3}}

Which of the following represents the completely simplified expression?

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Cevap: 1

Cevap

1
Both the entire complex numerator and the entire complex denominator independently simplify to xyx - y. Consequently, dividing the numerator xyx - y by the denominator xyx - y gives 11.

Adım Adım Çözüm

1
Simplify the first term of the main numerator
\frac{x^3 + y^3}{x^2 - y^2} = \frac{(x + y)(x^2 - xy + y^2)}{(x - y)(x + y)} = \frac{x^2 - xy + y^2}{x - y}
Factor the sum of cubes in the numerator and the difference of squares in the denominator, then cancel the common factor (x+y)(x + y).
2
Simplify the second term of the main numerator
\frac{x^2y - xy^2}{(x - y)^2} = \frac{xy(x - y)}{(x - y)^2} = \frac{xy}{x - y}
Factor out the greatest common factor xyxy from the numerator and cancel one factor of (xy)(x - y).
3
Subtract the simplified terms in the main numerator
\frac{x^2 - xy + y^2}{x - y} - \frac{xy}{x - y} = \frac{x^2 - 2xy + y^2}{x - y} = \frac{(x - y)^2}{x - y} = x - y
Combine the numerators over the common denominator (xy)(x - y), factor the perfect square trinomial x22xy+y2=(xy)2x^2 - 2xy + y^2 = (x - y)^2, and simplify.
4
Simplify the main denominator
\frac{x^4 - y^4}{x^3 + x^2y + xy^2 + y^3} = \frac{(x - y)(x + y)(x^2 + y^2)}{x^2(x + y) + y^2(x + y)} = \frac{(x - y)(x + y)(x^2 + y^2)}{(x + y)(x^2 + y^2)} = x - y
Factor the numerator using difference of squares twice, factor the denominator by grouping, and cancel common factors (x+y)(x2+y2)(x + y)(x^2 + y^2).
5
Divide the main numerator by the main denominator
\frac{x - y}{x - y} = 1
Divide the simplified main numerator (xyx - y) by the simplified main denominator (xyx - y).

Anahtar Kavram

Multi-step algebraic expression simplification using special factoring identities (sum/difference of cubes, difference of squares, quadratic trinomials, and factoring by grouping).
Tahmini Süre:2m 0s
Soru 2032Soru

A textile mill uses two weaving looms, Loom PP and Loom QQ, to produce a fabric blend composed of silk, wool, and cotton.

- Loom PP produces silk, wool, and cotton in the ratio 2:3:52 : 3 : 5 by weight, operating at a constant output rate of 120 kg per hour120\text{ kg per hour}.
- Loom QQ produces silk, wool, and cotton in the ratio 1:4:31 : 4 : 3 by weight, operating at a constant output rate of 160 kg per hour160\text{ kg per hour}.

If both looms operate simultaneously for 5 hours, what is the ratio of the total weight of wool produced to the total weight of cotton produced in the combined output?

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Cevap: 29:3029 : 30

Cevap

The ratio of the total weight of wool produced to the total weight of cotton produced is 29:3029 : 30.
To find the overall ratio of wool to cotton, determine the actual mass of each material produced per hour by each machine. Loom PP outputs 310×120=36 kg\frac{3}{10} \times 120 = 36\text{ kg} of wool and 510×120=60 kg\frac{5}{10} \times 120 = 60\text{ kg} of cotton per hour. Loom QQ outputs 48×160=80 kg\frac{4}{8} \times 160 = 80\text{ kg} of wool and 38×160=60 kg\frac{3}{8} \times 160 = 60\text{ kg} of cotton per hour. Combining both looms yields 116 kg116\text{ kg} of wool and 120 kg120\text{ kg} of cotton per hour. Over 5 hours, the combined output is 580 kg580\text{ kg} of wool and 600 kg600\text{ kg} of cotton. The ratio of total wool to total cotton is 580:600580 : 600, which simplifies to 29:3029 : 30.

Adım Adım Çözüm

1
Calculate the hourly production rates of wool and cotton for Loom PP.
Loom PP produces fabric at 120 kg/hr120\text{ kg/hr} with ratio parts 2+3+5=102 + 3 + 5 = 10.
- Wool rate from P=310×120=36 kg/hrP = \frac{3}{10} \times 120 = 36\text{ kg/hr}
- Cotton rate from P=510×120=60 kg/hrP = \frac{5}{10} \times 120 = 60\text{ kg/hr}
Converting the ratio into component rates by multiplying each component's fraction by Loom PP's total hourly output.
2
Calculate the hourly production rates of wool and cotton for Loom QQ.
Loom QQ produces fabric at 160 kg/hr160\text{ kg/hr} with ratio parts 1+4+3=81 + 4 + 3 = 8.
- Wool rate from Q=48×160=80 kg/hrQ = \frac{4}{8} \times 160 = 80\text{ kg/hr}
- Cotton rate from Q=38×160=60 kg/hrQ = \frac{3}{8} \times 160 = 60\text{ kg/hr}
Converting the ratio into component rates by multiplying each component's fraction by Loom QQ's total hourly output.
3
Determine total quantities produced over the 5-hour period.
Total wool =(36+80)×5=116×5=580 kg= (36 + 80) \times 5 = 116 \times 5 = 580\text{ kg}.
Total cotton =(60+60)×5=120×5=600 kg= (60 + 60) \times 5 = 120 \times 5 = 600\text{ kg}.
Combining the hourly outputs from both machines and multiplying by the total duration of 5 hours.
4
Compute and simplify the ratio of total wool to total cotton.
\text{Ratio} = \frac{580}{600} = \frac{29}{30},whichisexpressedas, which is expressed as 29 : 30$.
Dividing both terms of the ratio by their greatest common divisor, 20.

Anahtar Kavram

Combining weighted rates across multiple ratio-based sub-components
Tahmini Süre:2m 0s
Soru 2033Soru

In his 1890 treatise on comparative philology, historian Julian Thorne reexamined the formalization of sound laws in historical linguistics. Mid-nineteenth-century scholars often viewed language shifts as arbitrary historical accidents, whereas later Neogrammarians insisted that phonetic change operated with absolute, exceptionless necessity. Thorne contends that in their eagerness to establish linguistics as a rigorous science, these theorists put the cart before the horse by treating abstract, retrospective regularities as the primary engine driving speech transformation. In Thorne’s estimation, the codified sound laws were merely descriptive summaries compiled from thousands of individual spoken interactions, rather than pre-existing structural imperatives that dictated how speakers altered their pronunciation over time. By mistaking the observed outcome of linguistic evolution for its initiating cause, the Neogrammarians inverted the proper relationship between living language and theoretical abstraction.

Which of the following best captures the conceptual error described by the author's use of the phrase "put the cart before the horse"?

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Cevap: Reversing the logical relationship between an observed outcome and its underlying cause

Cevap

Reversing the logical relationship between an observed outcome and its underlying cause
The correct answer accurately identifies the metaphorical meaning of 'put the cart before the horse' in context. The passage explicitly states that the Neogrammarians treated retrospective summaries of language (the effect/outcome) as the driving force behind speech transformation (the cause), thereby inverting the natural causal sequence.

Adım Adım Çözüm

1
Locate the target phrase within the passage text
The phrase appears when describing how Neogrammarians treated 'abstract, retrospective regularities as the primary engine driving speech transformation.'
Contextual analysis is required to determine how the figurative phrase functions in this specific argument.
2
Analyze the surrounding elaboration provided by the author
The author explicitly clarifies the phrase in the subsequent sentences: the theorists mistook 'the observed outcome of linguistic evolution for its initiating cause.'
The author provides a direct contextual definition of the figurative expression immediately following its use.
3
Match the contextual meaning to the correct option while eliminating distractors
The choice describing the reversal of the logical relationship between an observed outcome and its underlying cause accurately reflects the inverted causal order described by the idiom.
The idiom 'put the cart before the horse' metaphorically signifies placing an effect or secondary item before its primary cause.

Anahtar Kavram

Interpreting Idiomatic Usage and Figurative Language in Context
Tahmini Süre:1m 30s
Soru 2034Soru

Let n=2a3b5cn = 2^a \cdot 3^b \cdot 5^c be a positive integer, where aa, bb, and cc are non-negative integers. If the greatest common divisor of nn and 360360 is 4545, and the least common multiple of nn and 9090 is 450450, what is the value of a+b+ca + b + c?

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Cevap: 4

Cevap

The value of a+b+ca + b + c is 44.
Prime factorizing the given values yields 360=233251360 = 2^3 \cdot 3^2 \cdot 5^1, 45=20325145 = 2^0 \cdot 3^2 \cdot 5^1, 90=21325190 = 2^1 \cdot 3^2 \cdot 5^1, and 450=213252450 = 2^1 \cdot 3^2 \cdot 5^2. Because gcd(n,360)=45\gcd(n, 360) = 45, taking the minimum exponent of 2 implies min(a,3)=0\min(a, 3) = 0, so a=0a = 0. Taking the minimum exponent of 3 implies b2b \ge 2, and for 5 implies c1c \ge 1. Next, using lcm(n,90)=450\text{lcm}(n, 90) = 450, taking the maximum exponent of 3 gives max(b,2)=2\max(b, 2) = 2, which forces b=2b = 2. Taking the maximum exponent of 5 gives max(c,1)=2\max(c, 1) = 2, which forces c=2c = 2. Therefore, a+b+c=0+2+2=4a + b + c = 0 + 2 + 2 = 4.

Adım Adım Çözüm

1
Express all given integers in their prime factorizations.
360=233251360 = 2^3 \cdot 3^2 \cdot 5^1, 45=3251=20325145 = 3^2 \cdot 5^1 = 2^0 \cdot 3^2 \cdot 5^1, 90=21325190 = 2^1 \cdot 3^2 \cdot 5^1, and 450=213252450 = 2^1 \cdot 3^2 \cdot 5^2.
Prime factorizations allow determination of exponents using exponent rules for GCD and LCM.
2
Apply the GCD condition gcd(n,360)=45\gcd(n, 360) = 45.
min(a,3)=0    a=0\min(a, 3) = 0 \implies a = 0, min(b,2)=2    b2\min(b, 2) = 2 \implies b \ge 2, and min(c,1)=1    c1\min(c, 1) = 1 \implies c \ge 1.
The greatest common divisor takes the minimum exponent for each prime factor shared between the numbers.
3
Apply the LCM condition lcm(n,90)=450\text{lcm}(n, 90) = 450 using a=0a = 0.
max(b,2)=2    b2\max(b, 2) = 2 \implies b \le 2 (so b=2b = 2), and max(c,1)=2    c=2\max(c, 1) = 2 \implies c = 2.
The least common multiple takes the maximum exponent for each prime factor.
4
Calculate the sum a+b+ca + b + c.
a+b+c=0+2+2=4a + b + c = 0 + 2 + 2 = 4.
Adding the individual prime factor exponents yields the requested sum.

Anahtar Kavram

Relating prime factor exponents to GCD (minimum powers) and LCM (maximum powers)
Tahmini Süre:1m 30s
Soru 2035Soru

If xx is a positive real number such that x34=27x^{\frac{3}{4}} = 27, what is the value of x12x^{-\frac{1}{2}}?

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Cevap: 19\frac{1}{9}

Cevap

19\frac{1}{9}
Raising both sides of x34=27x^{\frac{3}{4}} = 27 to the power of 43\frac{4}{3} gives x=(33)43=34=81x = (3^3)^{\frac{4}{3}} = 3^4 = 81. Substituting x=81x = 81 into x12x^{-\frac{1}{2}} gives 8112=181=1981^{-\frac{1}{2}} = \frac{1}{\sqrt{81}} = \frac{1}{9}.

Adım Adım Çözüm

1
Solve for xx in the equation x34=27x^{\frac{3}{4}} = 27.
x=2743=(33)43=34=81x = 27^{\frac{4}{3}} = (3^3)^{\frac{4}{3}} = 3^4 = 81
Raise both sides to the power of 43\frac{4}{3} to isolate xx.
2
Evaluate x12x^{-\frac{1}{2}} for x=81x = 81.
8112=18112=181=1981^{-\frac{1}{2}} = \frac{1}{81^{\frac{1}{2}}} = \frac{1}{\sqrt{81}} = \frac{1}{9}
Apply the negative exponent rule an=1ana^{-n} = \frac{1}{a^n} and the fractional exponent rule a12=aa^{\frac{1}{2}} = \sqrt{a}.

Anahtar Kavram

Fractional and Negative Exponents
Tahmini Süre:1m 30s
Soru 2036Soru

An executive is monitoring two independent corporate projects, Project Alpha and Project Beta. Based on historical performance, the probability that Project Alpha meets its deadline is 45\frac{4}{5}, and the probability that Project Beta meets its deadline is 34\frac{3}{4}. What is the probability that exactly one of the two projects meets its deadline?

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Cevap: 720\frac{7}{20}

Cevap

The probability that exactly one project meets its deadline is 720\frac{7}{20}.
The event 'exactly one project meets its deadline' consists of two mutually exclusive scenarios: (1) Alpha meets its deadline and Beta does not, or (2) Alpha misses its deadline and Beta meets it. Using independence, the probability of Scenario 1 is 45×(134)=45×14=420\frac{4}{5} \times \left(1 - \frac{3}{4}\right) = \frac{4}{5} \times \frac{1}{4} = \frac{4}{20}. The probability of Scenario 2 is (145)×34=15×34=320\left(1 - \frac{4}{5}\right) \times \frac{3}{4} = \frac{1}{5} \times \frac{3}{4} = \frac{3}{20}. Summing these mutually exclusive probabilities gives 420+320=720\frac{4}{20} + \frac{3}{20} = \frac{7}{20}.

Adım Adım Çözüm

1
Determine the probabilities of individual events and their complements.
P(Alpha meets)=45P(\text{Alpha meets}) = \frac{4}{5}, P(Alpha misses)=145=15P(\text{Alpha misses}) = 1 - \frac{4}{5} = \frac{1}{5}. P(Beta meets)=34P(\text{Beta meets}) = \frac{3}{4}, P(Beta misses)=134=14P(\text{Beta misses}) = 1 - \frac{3}{4} = \frac{1}{4}.
To find the probability of specific outcome combinations, the complementary probabilities for each independent event are required.
2
Identify the mutually exclusive cases that satisfy the condition 'exactly one project meets its deadline'.
Case 1: Alpha meets and Beta misses. Case 2: Alpha misses and Beta meets.
The event 'exactly one' consists of two distinct, non-overlapping scenarios.
3
Calculate the joint probability for each case using independence.
Case 1 probability: 45×14=420\frac{4}{5} \times \frac{1}{4} = \frac{4}{20}. Case 2 probability: 15×34=320\frac{1}{5} \times \frac{3}{4} = \frac{3}{20}.
Since the projects operate independently, joint probabilities are found by multiplying individual event probabilities.
4
Add the probabilities of the mutually exclusive cases.
420+320=720\frac{4}{20} + \frac{3}{20} = \frac{7}{20}.
For mutually exclusive events, the total probability of either case occurring is the sum of their individual probabilities.

Anahtar Kavram

Probability of Independent Events and Mutually Exclusive Cases
Soru 2037Soru

A digital archive charges an annual subscription fee of $120\$120, which includes 5050 free document downloads per year. For each additional document downloaded beyond the first 5050, the archive charges a flat rate of $1.50\$1.50. If a research group paid a total of $231\$231 to the archive last year, how many total documents did the research group download?

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Cevap: 124

Cevap

The total number of documents downloaded by the research group last year was 124.
Subtracting the base subscription fee of 120fromthetotalpaymentof120 from the total payment of 231 leaves 111spentstrictlyonextradownloads.Dividing111 spent strictly on extra downloads. Dividing 111 by the $1.50 per-document rate yields 74 extra downloads. Adding the 50 included free downloads gives a total of 124 documents downloaded.

Adım Adım Çözüm

1
Define the linear equation representing total cost.
120+1.50(x50)=231120 + 1.50(x - 50) = 231, where xx represents the total number of documents downloaded.
The base subscription fee is 120,andtheperdocumentrateof120, and the per-document rate of 1.50 applies only to documents in excess of the initial 50 free documents.
2
Isolate the variable term by subtracting the base subscription fee from both sides.
1.50(x50)=231120=1111.50(x - 50) = 231 - 120 = 111
This determines the portion of the total cost that resulted strictly from additional downloads.
3
Solve for the number of additional documents (x50)(x - 50).
x50=1111.50=74x - 50 = \frac{111}{1.50} = 74
Dividing the extra cost of 111bytheperdocumentrateof111 by the per-document rate of 1.50 gives the exact count of extra downloads.
4
Add the initial 50 free documents to find the total document count xx.
x=74+50=124x = 74 + 50 = 124
The question asks for the total documents downloaded, which combines the 50 free downloads and the 74 additional paid downloads.

Anahtar Kavram

Linear Equations in One Variable
Tahmini Süre:1m 30s
Soru 2038Soru

A chemical processing tank receives two liquid solutions, Solution XX and Solution YY, from separate inlet pipes.

- Solution XX contains chemical AA and water in a volume ratio of 3:23:2 and enters the tank at a constant rate of 150150 liters per hour.
- Solution YY contains chemical AA and water in a volume ratio of 1:41:4 and enters the tank at a constant rate of 250250 liters per hour.

Both inlet pipes run simultaneously into an initially empty tank for 44 hours. After 44 hours, the inlet pipes are shut off. To adjust the mixture, pure chemical AA is added to the tank at a constant rate of 5050 liters per hour, while water is continuously drained from the tank at a constant rate of 3030 liters per hour.

How many hours must this adjustment process run until the volume of chemical AA in the tank is equal to the volume of water in the tank?

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Cevap: 6

Cevap

6
To find the time tt when the volumes of chemical A and water in the tank are equal, first determine the initial quantities contributed by both solutions during the 4-hour filling period. Solution X provides 150×4=600150 \times 4 = 600 liters total, containing 35×600=360\frac{3}{5} \times 600 = 360 liters of chemical A and 25×600=240\frac{2}{5} \times 600 = 240 liters of water. Solution Y provides 250×4=1000250 \times 4 = 1000 liters total, containing 15×1000=200\frac{1}{5} \times 1000 = 200 liters of chemical A and 45×1000=800\frac{4}{5} \times 1000 = 800 liters of water. Adding these amounts yields 360+200=560360 + 200 = 560 liters of chemical A and 240+800=1040240 + 800 = 1040 liters of water. In the adjustment phase of tt hours, chemical A increases at 5050 L/hr to 560+50t560 + 50t, while water decreases at 3030 L/hr to 104030t1040 - 30t. Equating the two expressions gives 560+50t=104030t560 + 50t = 1040 - 30t, which simplifies to 80t=48080t = 480, resulting in t=6t = 6 hours.

Adım Adım Çözüm

1
Determine the volumes of chemical A and water supplied by Solution X during the first 4 hours.
Solution X delivers 600 liters in total, consisting of 360 liters of chemical A and 240 liters of water.
Solution X flows at 150 L/hr for 4 hours (150 * 4 = 600 L) with a 3:2 chemical A to water ratio, meaning chemical A represents 3/5 of the total volume and water represents 2/5.
2
Determine the volumes of chemical A and water supplied by Solution Y during the first 4 hours.
Solution Y delivers 1000 liters in total, consisting of 200 liters of chemical A and 800 liters of water.
Solution Y flows at 250 L/hr for 4 hours (250 * 4 = 1000 L) with a 1:4 chemical A to water ratio, meaning chemical A represents 1/5 of the total volume and water represents 4/5.
3
Calculate the total initial quantities of chemical A and water present in the tank prior to the adjustment phase.
Total chemical A = 560 liters; Total water = 1040 liters.
Sum the quantities from both solutions: Chemical A = 360 + 200 = 560 L; Water = 240 + 800 = 1040 L.
4
Formulate linear expressions representing the total volume of chemical A and water after t hours of adjustment.
Chemical A volume = 560 + 50t; Water volume = 1040 - 30t.
Pure chemical A is added at 50 L/hr, increasing its total volume, while water is drained at 30 L/hr, reducing its total volume.
5
Set the two component volume expressions equal to each other and solve for t.
t = 6 hours.
Solving 560 + 50t = 1040 - 30t leads to 80t = 480, which yields t = 6.

Anahtar Kavram

Multi-stream mixture rate integration and ratio equality modeling
Soru 2039Soru

For all real numbers xx and yy such that x2+xy+y20x^2 + xy + y^2 \neq 0, which of the following expressions are equivalent to x6y6x2+xy+y2\frac{x^6 - y^6}{x^2 + xy + y^2}? Select all such expressions.

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Cevap: (x2y2)(x2xy+y2)(x^2 - y^2)(x^2 - xy + y^2); (xy)(x3+y3)(x - y)(x^3 + y^3); x4x3y+xy3y4x^4 - x^3 y + x y^3 - y^4

Cevap

The equivalent expressions are (x2y2)(x2xy+y2)(x^2 - y^2)(x^2 - xy + y^2), (xy)(x3+y3)(x - y)(x^3 + y^3), and x4x3y+xy3y4x^4 - x^3y + xy^3 - y^4.
Factoring the numerator x6y6x^6 - y^6 as a difference of squares yields (x3y3)(x3+y3)(x^3 - y^3)(x^3 + y^3). Applying the difference of cubes identity x3y3=(xy)(x2+xy+y2)x^3 - y^3 = (x - y)(x^2 + xy + y^2) enables cancellation of the non-zero denominator x2+xy+y2x^2 + xy + y^2, leaving (xy)(x3+y3)(x - y)(x^3 + y^3). Expanding this product gives x4x3y+xy3y4x^4 - x^3y + xy^3 - y^4. Furthermore, factoring x3+y3x^3 + y^3 as (x+y)(x2xy+y2)(x + y)(x^2 - xy + y^2) and regrouping (xy)(x+y)(x - y)(x + y) gives (x2y2)(x2xy+y2)(x^2 - y^2)(x^2 - xy + y^2). Consequently, the three valid equivalent forms are (x2y2)(x2xy+y2)(x^2 - y^2)(x^2 - xy + y^2), (xy)(x3+y3)(x - y)(x^3 + y^3), and x4x3y+xy3y4x^4 - x^3y + xy^3 - y^4.

Adım Adım Çözüm

1
Factor the numerator x6y6x^6 - y^6 as a difference of squares.
x6y6=(x3)2(y3)2=(x3y3)(x3+y3)x^6 - y^6 = (x^3)^2 - (y^3)^2 = (x^3 - y^3)(x^3 + y^3)
Applying the difference of squares identity a2b2=(ab)(a+b)a^2 - b^2 = (a - b)(a + b) with a=x3a = x^3 and b=y3b = y^3.
2
Apply the difference of cubes identity to x3y3x^3 - y^3.
x3y3=(xy)(x2+xy+y2)x^3 - y^3 = (x - y)(x^2 + xy + y^2)
This reveals the non-zero quadratic factor present in the denominator.
3
Substitute into the original fraction and cancel the common factor (x2+xy+y2)(x^2 + xy + y^2).
(xy)(x2+xy+y2)(x3+y3)x2+xy+y2=(xy)(x3+y3)\frac{(x - y)(x^2 + xy + y^2)(x^3 + y^3)}{x^2 + xy + y^2} = (x - y)(x^3 + y^3)
Since x2+xy+y20x^2 + xy + y^2 \neq 0, dividing numerator and denominator by (x2+xy+y2)(x^2 + xy + y^2) simplifies the expression to (xy)(x3+y3)(x - y)(x^3 + y^3).
4
Expand (xy)(x3+y3)(x - y)(x^3 + y^3) to check for equivalent expanded polynomial forms.
(xy)(x3+y3)=x4+xy3x3yy4=x4x3y+xy3y4(x - y)(x^3 + y^3) = x^4 + xy^3 - x^3y - y^4 = x^4 - x^3y + xy^3 - y^4
Distributing terms verifies polynomial equivalence.
5
Factor x3+y3x^3 + y^3 and regroup to find another equivalent factored representation.
(xy)(x3+y3)=(xy)(x+y)(x2xy+y2)=(x2y2)(x2xy+y2)(x - y)(x^3 + y^3) = (x - y)(x + y)(x^2 - xy + y^2) = (x^2 - y^2)(x^2 - xy + y^2)
Applying the sum of cubes identity x3+y3=(x+y)(x2xy+y2)x^3 + y^3 = (x + y)(x^2 - xy + y^2) and combining (xy)(x+y)=x2y2(x - y)(x + y) = x^2 - y^2.

Anahtar Kavram

Factoring higher-degree algebraic expressions using difference of squares and sum/difference of cubes identities
Soru 2040Soru

A positive integer NN has exactly 1212 positive divisors. If the greatest common divisor of NN and 3535 is 77, and NN is a multiple of 66, which of the following values could be equal to NN? Indicate all such values.

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Cevabı ve açıklamayı göster

Cevap: 8484; 126126; 294294

Cevap

The positive integer NN could be equal to 8484, 126126, or 294294.
The integer NN must contain the prime factors 22, 33, and 77, but not 55. For NN to have exactly 1212 divisors, its prime factorization exponent set {a,b,c}\{a,b,c\} must satisfy (a+1)(b+1)(c+1)=12(a+1)(b+1)(c+1) = 12, which restricts the exponents to a permutation of {1,1,2}\{1, 1, 2\}. Evaluating the three permutations yields 8484, 126126, and 294294.

Adım Adım Çözüm

1
Analyze the conditions given for NN.
Since NN is a multiple of 66, 2N2 \mid N and 3N3 \mid N. Since gcd(N,35)=7\gcd(N, 35) = 7, 7N7 \mid N and 5N5 \nmid N. Thus, NN must have prime factors 2,3,72, 3, 7 and no prime factor of 55.
Establishing the prime factors of NN based on divisibility and GCD conditions.
2
Determine the prime factorization form and divisor count.
Let N=2a3b7cN = 2^a \cdot 3^b \cdot 7^c, where a1,b1,c1a \ge 1, b \ge 1, c \ge 1. The number of divisors is given by (a+1)(b+1)(c+1)=12(a+1)(b+1)(c+1) = 12.
The total number of positive divisors of a prime-factored integer piei\prod p_i^{e_i} is (ei+1)\prod (e_i+1).
3
Find all valid exponent combinations (a,b,c)(a, b, c).
The factors of 1212 into three integers each 2\ge 2 are 2×2×32 \times 2 \times 3. Therefore, the set of exponents {a,b,c}\{a, b, c\} must be a permutation of {1,1,2}\{1, 1, 2\}.
Each exponent increment (e+1)(e+1) must be at least 22 since every prime 2,3,72, 3, 7 is present.
4
Calculate the possible numerical values of NN.
Case 1: 223171=842^2 \cdot 3^1 \cdot 7^1 = 84.
Case 2: 213271=1262^1 \cdot 3^2 \cdot 7^1 = 126.
Case 3: 213172=2942^1 \cdot 3^1 \cdot 7^2 = 294.
Evaluating all three possible permutations of exponents for prime bases 2,3,2, 3, and 77.

Anahtar Kavram

Prime Factorization, Divisor Count Formula, and GCD Constraints
ÖncekiSayfa 102 / 107Sonraki
Tüm alıştırma soruları — GRE General Test | Examkin