Tüm alıştırma soruları

13931 soru

Soru 4181Soru

A biased four-sector spinner has sectors labeled 1, 2, 3, and 4. The theoretical probabilities of landing on sectors 1, 2, and 3 are in the ratio 1:2:21 : 2 : 2, respectively, while the theoretical probability of landing on sector 4 is 0.200.20. In an experiment consisting of 200200 spins, sector 2 was recorded 8080 times and sector 4 was recorded 6060 times. What is the positive difference between the expected number of even outcomes in 500500 future spins based on the experimental probability and that based on the theoretical probability?

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Cevap: 9090

Cevap

90
The theoretical probability of getting an even outcome (sector 2 or 4) is P(2)+P(4)=0.32+0.20=0.52P(2) + P(4) = 0.32 + 0.20 = 0.52, which predicts 500×0.52=260500 \times 0.52 = 260 even outcomes in 500500 spins. Empirically, even outcomes occurred 80+60=14080 + 60 = 140 times in 200200 spins, giving an experimental probability of 140/200=0.70140 / 200 = 0.70 and an estimated frequency of 500×0.70=350500 \times 0.70 = 350. The positive difference between these two expected values is 350260=90350 - 260 = 90.

Adım Adım Çözüm

1
Calculate the theoretical probabilities for each sector
P(1)=0.16P(1) = 0.16, P(2)=0.32P(2) = 0.32, P(3)=0.32P(3) = 0.32, P(4)=0.20P(4) = 0.20
Since P(4)=0.20P(4) = 0.20, the remaining probability 10.20=0.801 - 0.20 = 0.80 is shared among sectors 1, 2, and 3 in the ratio 1:2:21 : 2 : 2 (total 5 parts). Each part equals 0.80/5=0.160.80 / 5 = 0.16.
2
Determine the theoretical probability and expected frequency of an even outcome
Ptheo(Even)=0.52P_{\text{theo}}(\text{Even}) = 0.52; Expected frequency in 500 spins =260= 260
The even outcomes are sectors 2 and 4. Ptheo(Even)=P(2)+P(4)=0.32+0.20=0.52P_{\text{theo}}(\text{Even}) = P(2) + P(4) = 0.32 + 0.20 = 0.52. In 500500 spins, 500×0.52=260500 \times 0.52 = 260.
3
Calculate the experimental probability and expected frequency of an even outcome
Pexp(Even)=0.70P_{\text{exp}}(\text{Even}) = 0.70; Expected frequency in 500 spins =350= 350
Out of 200200 spins, even outcomes occurred 80+60=14080 + 60 = 140 times. Pexp(Even)=140/200=0.70P_{\text{exp}}(\text{Even}) = 140 / 200 = 0.70. In 500500 spins, 500×0.70=350500 \times 0.70 = 350.
4
Find the positive difference between the two expected values
350260=90350 - 260 = 90
Subtracting the theoretical expected frequency from the experimental expected frequency gives 350260=90|350 - 260| = 90.

Anahtar Kavram

Experimental vs. Theoretical Probability and Expected Frequency
Soru 4182Soru

Find the smallest positive integer nn that simultaneously satisfies the linear modular congruences 3n5(mod13)3n \equiv 5 \pmod{13} and 4n2(mod9)4n \equiv 2 \pmod{9}.

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Cevap: 32

Cevap

The smallest positive integer satisfying both congruences is 32.
Solving the first congruence 3n5(mod13)3n \equiv 5 \pmod{13} gives n6(mod13)n \equiv 6 \pmod{13} (since 3×91(mod13)3 \times 9 \equiv 1 \pmod{13} and 5×9=456(mod13)5 \times 9 = 45 \equiv 6 \pmod{13}), which means nn can be written as 13k+613k + 6. Substituting this into the second congruence 4n2(mod9)4n \equiv 2 \pmod{9} yields 4(13k+6)2(mod9)    52k+242(mod9)4(13k + 6) \equiv 2 \pmod{9} \implies 52k + 24 \equiv 2 \pmod{9}. Reducing the coefficients modulo 9 gives 7k+62(mod9)    7k45(mod9)7k + 6 \equiv 2 \pmod{9} \implies 7k \equiv -4 \equiv 5 \pmod{9}. Multiplying by 4 (the modular inverse of 7 modulo 9) yields k202(mod9)k \equiv 20 \equiv 2 \pmod{9}. Setting k=2k = 2 yields the smallest positive integer n=13(2)+6=32n = 13(2) + 6 = 32.

Adım Adım Çözüm

1
Solve the first modular congruence 3n5(mod13)3n \equiv 5 \pmod{13} for nn
n6(mod13)n \equiv 6 \pmod{13}, which implies n=13k+6n = 13k + 6
Multiplying both sides by the modular inverse of 3 modulo 13 (which is 9) isolates nn.
2
Solve the second modular congruence 4n2(mod9)4n \equiv 2 \pmod{9} for nn
n5(mod9)n \equiv 5 \pmod{9}
Multiplying both sides by the modular inverse of 4 modulo 9 (which is 7) isolates nn.
3
Substitute n=13k+6n = 13k + 6 into n5(mod9)n \equiv 5 \pmod{9} and simplify modulo 9
4k8(mod9)4k \equiv 8 \pmod{9}
Reducing 13 modulo 9 yields 4k4k, and subtracting 6 from 5 yields 18(mod9)-1 \equiv 8 \pmod{9}.
4
Solve for kk and calculate the smallest positive integer nn
k2(mod9)k \equiv 2 \pmod{9}, giving n=13(2)+6=32n = 13(2) + 6 = 32
Setting the integer parameter kk to its minimum non-negative value 22 provides the smallest positive integer solution.

Anahtar Kavram

System of Linear Modular Congruences and Modular Inverses
Soru 4183Soru

What is the 10th10^{\text{th}} term of the arithmetic progression 3,7,11,15,3, 7, 11, 15, \dots?

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Cevap: 39

Cevap

The 10th10^{\text{th}} term of the arithmetic progression is 3939.
By applying the nthn^{\text{th}} term formula for an arithmetic progression Tn=a+(n1)dT_n = a + (n - 1)d with first term a=3a = 3, common difference d=4d = 4, and term index n=10n = 10, the calculation yields T10=3+(101)×4=3+36=39T_{10} = 3 + (10 - 1) \times 4 = 3 + 36 = 39.

Adım Adım Çözüm

1
Identify the key parameters of the arithmetic progression from the given sequence.
First term a=3a = 3, common difference d=73=4d = 7 - 3 = 4, and number of terms n=10n = 10.
These parameters are required to use the nthn^{\text{th}} term formula of an A.P.
2
Substitute the values into the formula Tn=a+(n1)dT_n = a + (n - 1)d.
T10=3+(101)×4T_{10} = 3 + (10 - 1) \times 4
The formula relates the nthn^{\text{th}} term to the first term, common difference, and term position.
3
Evaluate the mathematical expression.
T10=3+9×4=3+36=39T_{10} = 3 + 9 \times 4 = 3 + 36 = 39
Perform multiplication before addition according to standard order of operations.

Anahtar Kavram

nth term of an Arithmetic Progression
Soru 4184Soru

The newly appointed committee chairman promised that all members would strictly abide _____ the regulations established by the board. Which preposition correctly completes the sentence?

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Cevap: by

Cevap

The preposition 'by' correctly completes the phrase 'abide by', meaning to accept and obey a decision or rule.
The verb 'abide' conventionally pairs with the preposition 'by' to form the fixed phrasal verb meaning to follow or obey rules, laws, or agreements.

Adım Adım Çözüm

1
Identify the main verb requiring a prepositional complement in the sentence
The main verb is 'abide'.
The sentence tests the fixed prepositional collocation associated with the verb 'abide'.
2
Determine the correct fixed preposition for 'abide' when referring to rules or regulations
'Abide' takes the preposition 'by'.
In standard English grammar, 'abide by' is a fixed prepositional expression meaning to observe or conform to rules.

Anahtar Kavram

Dependent Prepositions and Fixed Verb-Preposition Collocations
Tahmini Süre:45s
Soru 4185Soru

Read the sentence carefully: 'Despite her strong personal reservations regarding the executive board's new corporate policy, the senior director chose to toe the line during the press briefing.' Which of the following options best conveys the meaning of the idiomatic expression 'toe the line' as used in the sentence?

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Cevap: strictly conform to the rules and expectations of authority

Cevap

strictly conform to the rules and expectations of authority
The idiom 'toe the line' means to follow established rules, standards, or orders strictly, particularly when expected by an organization or authority. In the context provided, the senior director put aside her personal doubts to publicly adhere to the official corporate stance.

Adım Adım Çözüm

1
Analyze the context of the sentence
The subject has 'strong personal reservations' but acts in a particular way during an official press briefing.
Understanding the contrast between private reservations and public conduct is essential to deciphering the intended meaning.
2
Determine the idiomatic meaning of 'toe the line'
'Toe the line' is an established English idiom meaning to conform strictly to established rules or authority.
Idioms cannot be interpreted literally; their accepted figurative meanings dictate sentence comprehension.

Anahtar Kavram

Idioms and Idiomatic Expressions
Soru 4186Soru

Which of the following groups consists exclusively of fundamental physical quantities?

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Cevap: Mass, thermodynamic temperature, and luminous intensity

Cevap

The group containing mass, thermodynamic temperature, and luminous intensity consists exclusively of fundamental physical quantities.
Mass, thermodynamic temperature, and luminous intensity are three of the seven internationally recognized SI base (fundamental) physical quantities.

Adım Adım Çözüm

1
Identify the seven fundamental SI physical quantities
The seven base quantities are length, mass, time, electric current, thermodynamic temperature, amount of substance, and luminous intensity.
Fundamental quantities are independent quantities that cannot be defined in terms of other physical quantities.
2
Evaluate each provided option against the list of base quantities
Electric charge, force, and weight are derived quantities. Only mass, thermodynamic temperature, and luminous intensity are all fundamental.
Any quantity derived by multiplying or dividing base quantities is derived.

Anahtar Kavram

Fundamental quantities are basic physical quantities that are independent of one another and form the basis from which derived quantities are obtained.
Soru 4187Soru

What is the measure, in degrees, of each interior angle of a regular octagon (an 8-sided regular polygon)?

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Cevap: 135

Cevap

Each interior angle of a regular octagon measures 135 degrees.
The sum of the interior angles of a polygon with nn sides is (n2)×180(n - 2) \times 180^\circ. For a regular octagon (n=8n = 8), the total interior angle sum is (82)×180=1080(8 - 2) \times 180^\circ = 1080^\circ. Since all 8 interior angles of a regular octagon are congruent, dividing the total sum by 8 yields 135135^\circ for each interior angle.

Adım Adım Çözüm

1
Find the sum of all interior angles of the regular octagon.
Sum of interior angles = (82)×180=6×180=1080(8 - 2) \times 180^\circ = 6 \times 180^\circ = 1080^\circ.
The sum of interior angles for any nn-sided polygon is (n2)×180(n - 2) \times 180^\circ.
2
Calculate the measure of a single interior angle.
Interior angle = 10808=135\frac{1080^\circ}{8} = 135^\circ.
In a regular polygon, all interior angles are equal in measure.

Anahtar Kavram

Interior Angle of a Regular Polygon
Soru 4188Soru
What is the value of xx that satisfies the exponential equation 42x+1×8x116x=32\frac{4^{2x + 1} \times 8^{x - 1}}{16^x} = 32?
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Cevap: 22

Cevap

The value of xx is 22.
Converting all terms to base 22 gives 24x+2×23x324x=25\frac{2^{4x+2} \times 2^{3x-3}}{2^{4x}} = 2^5. Combining the powers on the left side yields 23x1=252^{3x-1} = 2^5. Equating exponents gives 3x1=53x - 1 = 5, which solves to x=2x = 2.

Adım Adım Çözüm

1
Express all base numbers in terms of a common prime base (base 2).
4=224 = 2^2, 8=238 = 2^3, 16=2416 = 2^4, and 32=2532 = 2^5.
Converting all terms to powers of 2 enables the application of index laws.
2
Substitute these prime base powers into the original equation and expand exponents.
(22)2x+1×(23)x1(24)x=25    24x+2×23x324x=25\frac{(2^2)^{2x + 1} \times (2^3)^{x - 1}}{(2^4)^x} = 2^5 \implies \frac{2^{4x + 2} \times 2^{3x - 3}}{2^{4x}} = 2^5
Applying (am)n=amn(a^m)^n = a^{m \cdot n} requires multiplying the outer exponent by every term in the inner exponent.
3
Apply index laws for multiplication (am×an=am+na^m \times a^n = a^{m+n}) and division (am÷an=amna^m \div a^n = a^{m-n}) on the left-hand side.
2(4x+2)+(3x3)4x=25    23x1=252^{(4x + 2) + (3x - 3) - 4x} = 2^5 \implies 2^{3x - 1} = 2^5
Powers with the same base are combined by adding numerator exponents and subtracting denominator exponents.
4
Equate the exponents since the bases are identical, and solve for xx.
3x1=5    3x=6    x=23x - 1 = 5 \implies 3x = 6 \implies x = 2
If ax=aya^x = a^y for a>0a > 0 and a1a \neq 1, then x=yx = y.

Anahtar Kavram

Solving Exponential Equations using Laws of Indices
Tahmini Süre:1m 30s
Soru 4189Soru

Given the simultaneous equations x+2y=7x + 2y = 7 and x2+3xy+y2=19x^2 + 3xy + y^2 = 19, find the product of all possible values of yy that satisfy the system.

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Cevap: -30

Cevap

The product of all possible values of y that satisfy the system is -30.
Rearranging the linear equation gives x = 7 - 2y. Substituting this into the quadratic equation x^2 + 3xy + y^2 = 19 produces (7 - 2y)^2 + 3(7 - 2y)y + y^2 = 19. Expanding and combining like terms yields y^2 + 7y - 30 = 0. Solving for y gives y = 3 and y = -10. Multiplying these values together gives a product of -30.

Adım Adım Çözüm

1
Isolate x in the linear equation
x = 7 - 2y
Expressing one variable in terms of the other enables substitution into the quadratic equation.
2
Substitute x into the quadratic equation and expand
(7 - 2y)^2 + 3(7 - 2y)y + y^2 = 19
This reduces the system to a single quadratic equation in terms of y.
3
Simplify the resulting expression into standard quadratic form
y^2 + 7y - 30 = 0
Expanding yields (49 - 28y + 4y^2) + (21y - 6y^2) + y^2 = 19, which reduces to y^2 + 7y - 30 = 0.
4
Calculate the product of the roots of y
y_1 * y_2 = -30
By Vieta's formulas, the product of roots for y^2 + ay + b = 0 is b/1 = -30 (or factoring gives y = 3 and y = -10, with product 3 * (-10) = -30).

Anahtar Kavram

Solving simultaneous linear and quadratic equations via substitution and applying quadratic root properties
Tahmini Süre:2m 0s
Soru 4190Soru

The grouped frequency distribution table below shows the marks scored by 100100 candidates in a Mathematics screening test:

Class IntervalFrequency
101910 - 1915
202920 - 2925
303930 - 3940
404940 - 4920

Match each data representation component on the left with its correct calculated numerical value on the right.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Sector angle representing the modal class in a pie chart
Frequency density of the modal class for a histogram
Upper class boundary of the class interval immediately preceding the modal class
Cumulative frequency corresponding to the upper boundary of the median class on an ogive

Eşleşmeler

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Cevap

The sector angle matches 144144^\circ, frequency density matches 4.04.0, preceding upper class boundary matches 29.529.5, and median class cumulative frequency matches 8080.
The items match based on direct statistical computations: the modal sector angle is 144144^\circ, frequency density is 4.04.0, upper class boundary of the preceding interval is 29.529.5, and cumulative frequency at the upper boundary of the median class is 8080.

Adım Adım Çözüm

1
Determine the modal class and total frequency NN.
The highest frequency is 4040, so the modal class is 303930 - 39. Total frequency N=15+25+40+20=100N = 15 + 25 + 40 + 20 = 100.
Modal class identification is essential for pie chart sector, frequency density, and class boundary calculations.
2
Calculate the sector angle for the modal class in a pie chart.
Sector Angle =40100×360=144= \frac{40}{100} \times 360^\circ = 144^\circ.
The sector angle represents the class frequency as a fraction of total frequency multiplied by 360360^\circ.
3
Calculate the frequency density of the modal class.
Class boundary range for 303930 - 39 is 29.539.529.5 - 39.5, so width =10= 10. Frequency density =4010=4.0= \frac{40}{10} = 4.0.
Frequency density is defined as class frequency divided by class interval width.
4
Determine the preceding upper class boundary and the cumulative frequency for the median class.
Preceding interval is 202920 - 29, so its upper boundary is 29.529.5. Median is at position 5050 (in interval 303930 - 39). Cumulative frequency up to boundary 39.539.5 is 15+25+40=8015 + 25 + 40 = 80.
Class boundaries are midpoints between adjacent class limits, and cumulative frequency sums all preceding frequencies up to the upper boundary.

Anahtar Kavram

Interpretation and calculation of pie chart sector angles, histogram frequency densities, real class boundaries, and cumulative frequencies from grouped data.
Soru 4191Soru

If y=(2x+1)3y = (2x + 1)^3, find the value of dydx\frac{dy}{dx} at x=1x = 1.

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Cevap: 54

Cevap

54
Applying the chain rule gives dydx=3(2x+1)22=6(2x+1)2\frac{dy}{dx} = 3(2x + 1)^2 \cdot 2 = 6(2x + 1)^2. Evaluating at x=1x = 1 gives 6(3)2=546(3)^2 = 54.

Adım Adım Çözüm

1
Differentiate y=(2x+1)3y = (2x + 1)^3 using the chain rule.
dydx=6(2x+1)2\frac{dy}{dx} = 6(2x + 1)^2
According to the chain rule, ddx[un]=nun1dudx\frac{d}{dx}[u^n] = n u^{n-1} \cdot \frac{du}{dx}, where u=2x+1u = 2x + 1 and dudx=2\frac{du}{dx} = 2.
2
Evaluate the derivative at x=1x = 1.
dydxx=1=54\frac{dy}{dx}\Big|_{x=1} = 54
Substituting x=1x = 1 into 6(2x+1)26(2x + 1)^2 yields 6(3)2=546(3)^2 = 54.

Anahtar Kavram

Chain Rule for Differentiation
Soru 4192Soru

A micrometer screw gauge with a positive zero error of +0.04 mm+0.04\text{ mm} gives an observed reading of 2.46 mm2.46\text{ mm} when measuring the diameter of a thin wire. What is the actual diameter of the wire?

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Cevap: 2.42 mm2.42\text{ mm}

Cevap

The actual diameter of the wire is 2.42 mm2.42\text{ mm}.
To calculate the actual reading on a measuring instrument, use the relationship Actual Reading=Observed ReadingZero Error\text{Actual Reading} = \text{Observed Reading} - \text{Zero Error}. Subtracting +0.04 mm+0.04\text{ mm} from 2.46 mm2.46\text{ mm} yields 2.42 mm2.42\text{ mm}.

Adım Adım Çözüm

1
Identify the given readings
Observed reading = 2.46 mm2.46\text{ mm}, Zero error = +0.04 mm+0.04\text{ mm}
Extract values needed for zero error correction.
2
Apply zero error correction formula
Actual Reading=Observed ReadingZero Error=2.46 mm(+0.04 mm)=2.42 mm\text{Actual Reading} = \text{Observed Reading} - \text{Zero Error} = 2.46\text{ mm} - (+0.04\text{ mm}) = 2.42\text{ mm}
A positive zero error means the instrument reads higher than true zero, so the zero error must be subtracted from the observed reading.

Anahtar Kavram

Instrument Zero Error Correction
Tahmini Süre:45s
Soru 4193Soru

If y=e4xsinxy = e^{4x} - \sin x, what is dydx\frac{dy}{dx}?

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Cevap: 4e4xcosx4e^{4x} - \cos x

Cevap

4e4xcosx4e^{4x} - \cos x
Differentiating e4xe^{4x} gives 4e4x4e^{4x} by applying the chain rule, and differentiating sinx-\sin x yields cosx-\cos x. Combining these terms gives the correct derivative 4e4xcosx4e^{4x} - \cos x.

Adım Adım Çözüm

1
Apply the sum/difference rule of differentiation.
\frac{dy}{dx} = \frac{d}{dx}(e^{4x}) - \frac{d}{dx}(\sin x)
The derivative of a difference of two terms is the difference of their individual derivatives.
2
Differentiate the exponential term e4xe^{4x} using the chain rule.
ddx(e4x)=4e4x\frac{d}{dx}(e^{4x}) = 4e^{4x}
By the chain rule, \frac{d}{dx}(e^{k x}) = k e^{k x}.
3
Differentiate the trigonometric term sinx\sin x.
ddx(sinx)=cosx\frac{d}{dx}(\sin x) = \cos x
The standard derivative of sinx\sin x with respect to xx is cosx\cos x.
4
Combine the results.
\frac{dy}{dx} = 4e^{4x} - \cos x
Subtracting the derivative of sinx\sin x from the derivative of e4xe^{4x} gives the final answer.

Anahtar Kavram

Differentiation of Exponential and Trigonometric Functions
Soru 4194Soru
Find the real value of xx that satisfies the exponential equation 52x1×25x+1=125x+25^{2x - 1} \times 25^{x + 1} = 125^{x + 2}
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Cevap: 5

Cevap

The value of xx is 5.
By converting all terms to base 5 (25=5225 = 5^2 and 125=53125 = 5^3), the equation becomes 52x1×52(x+1)=53(x+2)5^{2x-1} \times 5^{2(x+1)} = 5^{3(x+2)}. Simplifying exponents gives 52x1×52x+2=53x+65^{2x-1} \times 5^{2x+2} = 5^{3x+6}. Adding the left-hand powers results in 54x+1=53x+65^{4x+1} = 5^{3x+6}. Equating the exponents yields 4x+1=3x+64x + 1 = 3x + 6, leading directly to x=5x = 5.

Adım Adım Çözüm

1
Express all terms with a common base of 5
52x1×52x+2=53x+65^{2x-1} \times 5^{2x+2} = 5^{3x+6}
Since 25=5225 = 5^2 and 125=53125 = 5^3, using index laws (am)n=amn(a^m)^n = a^{mn} allows all expressions to share base 5.
2
Apply the product rule of indices on the left side
54x+1=53x+65^{4x+1} = 5^{3x+6}
According to the product law am×an=am+na^m \times a^n = a^{m+n}, the powers are added: (2x1)+(2x+2)=4x+1(2x-1) + (2x+2) = 4x+1.
3
Equate powers of equal bases to solve for x
x=5x = 5
Since bases are equal, exponents must be equal: 4x+1=3x+6    4x3x=61    x=54x + 1 = 3x + 6 \implies 4x - 3x = 6 - 1 \implies x = 5.

Anahtar Kavram

Indices and Laws of Indices
Soru 4195Soru

In a probability experiment, two fair six-sided dice were rolled 180180 times, yielding an experimental probability of 518\frac{5}{18} for obtaining a sum divisible by 33. If mm additional consecutive rolls were conducted and every single one resulted in a sum divisible by 33, the updated overall experimental probability equaled the theoretical probability that the absolute difference between the numbers shown on two fair six-sided dice is at most 11. Calculate the value of mm.

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Cevap: 54

Cevap

54
The initial number of successful trials is 180×518=50180 \times \frac{5}{18} = 50. The theoretical probability of rolling two dice with an absolute difference of at most 11 is calculated by counting 66 outcomes with difference 00 and 1010 outcomes with difference 11, giving 1636=49\frac{16}{36} = \frac{4}{9}. Equating the updated experimental probability 50+m180+m\frac{50 + m}{180 + m} to 49\frac{4}{9} yields 9(50+m)=4(180+m)9(50 + m) = 4(180 + m), which simplifies to 5m=2705m = 270 or m=54m = 54.

Adım Adım Çözüm

1
Calculate the initial number of successful trials from the given experimental probability.
Initial successful outcomes = 180×518=50180 \times \frac{5}{18} = 50.
Experimental probability is defined as the number of successful trials divided by the total number of trials.
2
Calculate the theoretical probability that the absolute difference between two rolled six-sided dice is at most 1.
Favorable outcomes = 16, so P(theoretical)=1636=49P(\text{theoretical}) = \frac{16}{36} = \frac{4}{9}.
Outcomes with difference 0: (1,1),(2,2),(3,3),(4,4),(5,5),(6,6)(1,1), (2,2), (3,3), (4,4), (5,5), (6,6) (6 outcomes). Outcomes with difference 1: (1,2),(2,1),(2,3),(3,2),(3,4),(4,3),(4,5),(5,4),(5,6),(6,5)(1,2), (2,1), (2,3), (3,2), (3,4), (4,3), (4,5), (5,4), (5,6), (6,5) (10 outcomes). Total sample space =6×6=36= 6 \times 6 = 36.
3
Formulate the algebraic equation relating the updated experimental probability to the theoretical probability.
50+m180+m=49\frac{50 + m}{180 + m} = \frac{4}{9}.
Adding mm consecutive successful rolls increases both the number of successful outcomes (to 50+m50 + m) and the total number of trials (to 180+m180 + m).
4
Solve the equation for mm.
9(50+m)=4(180+m)    450+9m=720+4m    5m=270    m=549(50 + m) = 4(180 + m) \implies 450 + 9m = 720 + 4m \implies 5m = 270 \implies m = 54.
Cross-multiplication converts the rational expression into a linear equation.

Anahtar Kavram

Experimental and Theoretical Probability Synthesis
Tahmini Süre:3m 0s
Soru 4196Soru

A box contains 5050 marbles of three different colors: red, blue, and green. The theoretical probability of selecting a red marble at random is 310\frac{3}{10}. In a probability experiment, a marble was drawn with replacement 250250 times, resulting in a red marble being drawn 8585 times. What is the positive difference between the experimental probability and the theoretical probability of selecting a red marble?

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Cevap: 125\frac{1}{25}

Cevap

The positive difference between the experimental probability and the theoretical probability of selecting a red marble is 125\frac{1}{25}.
The experimental probability is the ratio of observed successful trials to total trials, which is 85250=1750\frac{85}{250} = \frac{17}{50}. The theoretical probability is given as 310=1550\frac{3}{10} = \frac{15}{50}. Subtracting the theoretical probability from the experimental probability gives 17501550=250=125\frac{17}{50} - \frac{15}{50} = \frac{2}{50} = \frac{1}{25}.

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1
Calculate the experimental probability (relative frequency) of drawing a red marble.
Experimental Probability=Number of successful outcomesTotal number of trials=85250=1750=0.34\text{Experimental Probability} = \frac{\text{Number of successful outcomes}}{\text{Total number of trials}} = \frac{85}{250} = \frac{17}{50} = 0.34
Experimental probability is calculated using empirical trial outcomes.
2
Identify the given theoretical probability of drawing a red marble.
Theoretical Probability=310=1550=0.30\text{Theoretical Probability} = \frac{3}{10} = \frac{15}{50} = 0.30
The theoretical probability is provided directly as 310\frac{3}{10}.
3
Compute the positive difference between experimental and theoretical probabilities.
Difference=17501550=250=125=0.04\text{Difference} = \frac{17}{50} - \frac{15}{50} = \frac{2}{50} = \frac{1}{25} = 0.04
Subtracting theoretical probability from experimental probability gives the required positive difference.

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Experimental vs Theoretical Probability
Tahmini Süre:1m 30s
Soru 4197Soru

The frequency table below shows the distribution of daily petrol consumption (in litres) recorded by 4040 commercial minibus drivers:

Daily Petrol Consumption (litres)Frequency (ff)
101410 - 1466
151915 - 191010
202420 - 241212
252925 - 2988
303430 - 3444

What is the mean daily petrol consumption of the minibus drivers?

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Cevap: 21.25 litres21.25\text{ litres}

Cevap

The mean daily petrol consumption is 21.25 litres21.25\text{ litres}.
The mean of a grouped frequency distribution is computed by multiplying the midpoint of each class interval by its frequency, summing these products, and dividing by the total frequency. For the given distribution, fx=850\sum fx = 850 and f=40\sum f = 40, giving a mean of 21.25 litres21.25\text{ litres}.

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1
Calculate the class mark (midpoint) xx for each class interval.
Midpoints are: 1212 for 101410 - 14, 1717 for 151915 - 19, 2222 for 202420 - 24, 2727 for 252925 - 29, and 3232 for 303430 - 34.
For grouped data, each class interval is represented by its midpoint.
2
Multiply each midpoint xx by its corresponding frequency ff to find fxfx.
6×12=726 \times 12 = 72, 10×17=17010 \times 17 = 170, 12×22=26412 \times 22 = 264, 8×27=2168 \times 27 = 216, 4×32=1284 \times 32 = 128.
This yields the total sum contribution of each class.
3
Find total frequency f\sum f and total sum of products fx\sum fx.
f=6+10+12+8+4=40\sum f = 6 + 10 + 12 + 8 + 4 = 40 and fx=72+170+264+216+128=850\sum fx = 72 + 170 + 264 + 216 + 128 = 850.
Required components for the grouped mean formula.
4
Calculate the mean xˉ=fxf\bar{x} = \frac{\sum fx}{\sum f}.
\bar{x} = \frac{850}{40} = 21.25\text{ litres}.
Applying the formula for the mean of grouped frequency distribution.

Anahtar Kavram

Grouped Mean Calculation using Midpoints
Tahmini Süre:1m 30s
Soru 4198Soru

Pump A can fill a water reservoir in 66 hours, while a drain pipe can empty the full reservoir in 1515 hours. Pump A is switched on to fill an empty reservoir while the drain pipe is accidentally left open. After 33 hours, an identical pump, Pump B, is also switched on to assist Pump A while the drain pipe remains open. How many total hours will it take for the reservoir to become completely full?

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Cevap: 5.625

Cevap

The total time required to fill the reservoir completely is 5.6255.625 hours.
To solve multi-stage work and rate problems involving opposing forces (filling vs. draining), calculate the net rate of change per unit of time for each stage. In stage one, Pump A adds 16\frac{1}{6} while the drain removes 115\frac{1}{15}, giving a net rate of 110\frac{1}{10} per hour. In 3 hours, 310\frac{3}{10} of the reservoir is filled, leaving 710\frac{7}{10}. In stage two, adding identical Pump B increases the filling rate to 2×16=132 \times \frac{1}{6} = \frac{1}{3}. Subtracting the drain rate 115\frac{1}{15} yields a net rate of 415\frac{4}{15} per hour. Dividing the remaining 710\frac{7}{10} by 415\frac{4}{15} gives 2.6252.625 hours. Adding the initial 3 hours yields a total of 5.6255.625 hours.

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1
Determine individual hourly rates
Pump A rate = +16+\frac{1}{6} reservoir/hr, Drain rate = 115-\frac{1}{15} reservoir/hr
Rate is the reciprocal of the time required to complete the full job.
2
Calculate net rate and progress for the first 3 hours
Net rate = 16115=110\frac{1}{6} - \frac{1}{15} = \frac{1}{10} reservoir/hr. Progress in 3 hours = 3×110=3103 \times \frac{1}{10} = \frac{3}{10} of the reservoir.
Only Pump A and the drain pipe are active during the initial 3-hour period.
3
Calculate remaining fraction of reservoir to be filled
Remaining portion = 1310=7101 - \frac{3}{10} = \frac{7}{10}
The total capacity of the reservoir is represented by 11 whole unit.
4
Calculate the combined rate after Pump B is added
New net rate = 16+16115=13115=415\frac{1}{6} + \frac{1}{6} - \frac{1}{15} = \frac{1}{3} - \frac{1}{15} = \frac{4}{15} reservoir/hr
Pump B is identical to Pump A, so its rate is also 16\frac{1}{6} reservoir/hr.
5
Find additional time needed and total time elapsed
Additional time = 7/104/15=710×154=218=2.625\frac{7/10}{4/15} = \frac{7}{10} \times \frac{15}{4} = \frac{21}{8} = 2.625 hours. Total time = 3+2.625=5.6253 + 2.625 = 5.625 hours.
Time equals remaining work divided by combined net rate, then added to elapsed time.

Anahtar Kavram

Work-Rate and Simultaneous Operations (Combined Filling and Emptying Rates)
Tahmini Süre:2m 30s
Soru 4199Soru

After hours of heated debate, the parliamentary committee reached a tacit agreement regarding the new fiscal policies, avoiding any explicit formal endorsement. Which of the following words is nearest in meaning to the underlined word as used in the sentence?

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Cevap: implicit

Cevap

The word nearest in meaning to 'tacit' is 'implicit'.
The word 'tacit' describes an agreement or understanding that is expressed or carried out without words, implied rather than stated. In the given sentence, the phrase 'avoiding any explicit formal endorsement' confirms that the agreement was unwritten and unspoken. Therefore, 'implicit' is the word nearest in meaning.

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1
Analyze the contextual clue in the sentence.
The clause 'avoiding any explicit formal endorsement' indicates that the agreement was unstated or implied rather than openly spoken.
Contextual contrast helps determine the precise meaning of the target word.
2
Evaluate the options for the closest contextual synonym.
'Implicit' means suggested though not directly expressed, which perfectly fits 'tacit'.
Matching contextual definition with option meanings identifies the correct synonym.

Anahtar Kavram

Synonyms and Words Nearest in Meaning
Soru 4200Soru

A physical quantity ZZ is defined as the ratio of the product of impulse and linear velocity to the product of electric current and electric potential difference. When ZZ is fully resolved into fundamental physical quantities, which fundamental quantity does ZZ represent?

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Cevap: Time

Cevap

Time
The correct answer is Time because reducing both the numerator (energy) and denominator (electrical power) to base fundamental dimensions yields ML2T2ML2T3=T\frac{M L^2 T^{-2}}{M L^2 T^{-3}} = T, which corresponds directly to the fundamental quantity of Time.

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1
Express impulse and velocity in terms of fundamental base quantities (Mass MM, Length LL, Time TT)
Impulse=Force×Time=MLT1\text{Impulse} = \text{Force} \times \text{Time} = M L T^{-1}. Velocity=LT1\text{Velocity} = L T^{-1}. Product =(MLT1)(LT1)=ML2T2= (M L T^{-1})(L T^{-1}) = M L^2 T^{-2}.
To evaluate the numerator in fundamental base dimensions.
2
Express electric current and potential difference in terms of fundamental base quantities
Current=I\text{Current} = I. Potential Difference=WorkCharge=ML2T2IT=ML2T3I1\text{Potential Difference} = \frac{\text{Work}}{\text{Charge}} = \frac{M L^2 T^{-2}}{I T} = M L^2 T^{-3} I^{-1}. Product =I×(ML2T3I1)=ML2T3= I \times (M L^2 T^{-3} I^{-1}) = M L^2 T^{-3}.
To evaluate the denominator in fundamental base dimensions.
3
Divide the numerator by the denominator to simplify quantity ZZ
Z=ML2T2ML2T3=M11L22T2(3)=T1Z = \frac{M L^2 T^{-2}}{M L^2 T^{-3}} = M^{1-1} L^{2-2} T^{-2 - (-3)} = T^1.
Determining the net fundamental quantity after all derived units cancel out.

Anahtar Kavram

Fundamental and Derived Quantities
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