Arithmetic

306 soru

Soru 121Soru

Two positive integers aa and bb have prime factorizations of the form a=2x×3y×5za = 2^x \times 3^y \times 5^z and b=2u×3v×5wb = 2^u \times 3^v \times 5^w, where x,y,z,u,v,wx, y, z, u, v, w are non-negative integers. The greatest common divisor (GCD) of aa and bb is 180180, and the least common multiple (LCM) of aa and bb is 54,00054,000. If aa has exactly 2424 positive divisors, what is the value of bb?

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Cevap: 18000

Cevap

18000
Prime factorizing GCD(a,b)=180=22×32×51\text{GCD}(a,b) = 180 = 2^2 \times 3^2 \times 5^1 and LCM(a,b)=54,000=24×33×53\text{LCM}(a,b) = 54,000 = 2^4 \times 3^3 \times 5^3 reveals that the pair of exponents for bases 2,3,52, 3, 5 are {2,4}\{2, 4\}, {2,3}\{2, 3\}, and {1,3}\{1, 3\} respectively. Applying the total divisor formula (x+1)(y+1)(z+1)=24(x+1)(y+1)(z+1) = 24 for aa, x+1x+1 must divide 2424. Since x{2,4}x \in \{2, 4\}, xx must be 22 (since 55 does not divide 2424). This leaves (y+1)(z+1)=8(y+1)(z+1) = 8. With y{2,3}y \in \{2, 3\}, y+1y+1 must be 44 (since 33 does not divide 88), giving y=3y = 3 and z=1z = 1. Thus, a=22×33×51a = 2^2 \times 3^3 \times 5^1. The remaining exponent choices for bb are u=4u = 4, v=2v = 2, and w=3w = 3, giving b=24×32×53=18,000b = 2^4 \times 3^2 \times 5^3 = 18,000.

Adım Adım Çözüm

1
Factorize GCD and LCM into prime bases.
GCD = 2^2 * 3^2 * 5^1; LCM = 2^4 * 3^3 * 5^3.
GCD represents the minimum prime exponents and LCM represents the maximum prime exponents of a and b.
2
Set up candidate exponent pairs for primes 2, 3, and 5.
{x, u} = {2, 4}, {y, v} = {2, 3}, and {z, w} = {1, 3}.
For any prime p, min(exp_p(a), exp_p(b)) = exp_p(GCD) and max(exp_p(a), exp_p(b)) = exp_p(LCM).
3
Solve for x, y, and z using the divisor count formula d(a) = (x+1)(y+1)(z+1) = 24.
x = 2, y = 3, z = 1.
If x = 4, then x+1 = 5, which is not a factor of 24. Thus x = 2. Then (y+1)(z+1) = 8. Since y in {2, 3}, y+1 = 4 implies y = 3 and z = 1.
4
Determine the exponents of b and calculate b.
u = 4, v = 2, w = 3, so b = 2^4 * 3^2 * 5^3 = 18,000.
Complementary values from the sets {x,u}, {y,v}, and {z,w} give the exponents for b.

Anahtar Kavram

Relationship between prime factor exponents in GCD, LCM, and divisor counting functions.
Soru 122Soru

An employee's annual salary was increased by 20%20\% at the beginning of 2024. At the end of 2024, the salary was decreased by 20%20\% from its updated value. At the beginning of 2025, the salary was increased by 10%10\% from its end-of-2024 value. If the initial salary before any of these changes was SS, which of the following statements must be true? Select all such statements.

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Cevap: The salary at the end of 2024 was 4%4\% less than the original salary SS.; The overall percentage change from the original salary SS to the salary at the beginning of 2025 is a 5.6%5.6\% increase.

Cevap

The statement that the salary at the end of 2024 was 4% less than the original salary S, and the statement that the overall percentage change from the original salary S to the salary at the beginning of 2025 is a 5.6% increase, are both correct.
The initial salary SS experiences successive changes: first multiplied by 1.201.20, then by 0.800.80, and finally by 1.101.10. At the end of 2024, the value is 1.20×0.80S=0.96S1.20 \times 0.80 S = 0.96S, which is 4%4\% less than SS. At the beginning of 2025, the value is 0.96S×1.10=1.056S0.96S \times 1.10 = 1.056S, which reflects a net increase of 5.6%5.6\% over the initial amount SS.

Adım Adım Çözüm

1
Calculate the salary after the first 20% increase at the beginning of 2024.
Salary = S×(1+0.20)=1.20SS \times (1 + 0.20) = 1.20S
An increase of 20% scales the initial value SS by a multiplier of 1.20.
2
Calculate the salary after the 20% decrease at the end of 2024.
Salary = 1.20S×(10.20)=1.20S×0.80=0.96S1.20S \times (1 - 0.20) = 1.20S \times 0.80 = 0.96S
The 20% decrease is calculated using the updated base of 1.20S1.20S, yielding 0.96S0.96S, which represents a 4% overall decrease from SS.
3
Calculate the salary after the 10% increase at the beginning of 2025.
Final Salary = 0.96S×(1+0.10)=0.96S×1.10=1.056S0.96S \times (1 + 0.10) = 0.96S \times 1.10 = 1.056S
The 10% increase is calculated using the base value of 0.96S0.96S.
4
Determine the net percent change from the original salary SS to the beginning of 2025.
Net Change = 1.056SSS×100%=0.056×100%=5.6%\frac{1.056S - S}{S} \times 100\% = 0.056 \times 100\% = 5.6\% increase.
Comparing the final multiplier 1.0561.056 to the original base multiplier 1.0001.000 shows a 5.6% overall growth.

Anahtar Kavram

Successive Percentage Changes and Base Value Shifts
Soru 123Soru

Let N=2a3b5cN = 2^a \cdot 3^b \cdot 5^c, where aa, bb, and cc are positive integers. The integer NN is divisible by 2424, has exactly 3636 positive integer divisors, and N5\frac{N}{5} is not divisible by 2525. What is the least possible value of a+b+ca + b + c?

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Cevap: 77

Cevap

7
The correct answer is 77. Since 24=233124 = 2^3 \cdot 3^1 divides NN, a3a \ge 3 and b1b \ge 1. The condition that N5\frac{N}{5} is not divisible by 2525 restricts cc to either 11 or 22. For c=2c=2, the divisor equation becomes (a+1)(b+1)(3)=36(a+1)(b+1)(3) = 36, so (a+1)(b+1)=12(a+1)(b+1) = 12. Taking a+1=4a+1=4 (a=3a=3) and b+1=3b+1=3 (b=2b=2) satisfies a3a \ge 3 and gives a minimal sum of a+b+c=3+2+2=7a+b+c = 3+2+2 = 7.

Adım Adım Çözüm

1
Analyze divisibility conditions on exponents
Since NN is divisible by 24=233124 = 2^3 \cdot 3^1, we must have a3a \ge 3 and b1b \ge 1. Since N5=2a3b5c1\frac{N}{5} = 2^a \cdot 3^b \cdot 5^{c-1} is not divisible by 25=5225 = 5^2, c1<2    c2c-1 < 2 \implies c \le 2. Because cc is a positive integer, cc can be 11 or 22.
Establish structural constraints on prime exponents from the divisibility statements.
2
Set up the total divisor formula
The total number of positive integer divisors of NN is (a+1)(b+1)(c+1)=36(a+1)(b+1)(c+1) = 36.
Apply the standard formula for counting divisors using prime factorization.
3
Evaluate candidate values for c=1c = 1 and c=2c = 2
If c=1c = 1, then c+1=2c+1 = 2, so (a+1)(b+1)=18(a+1)(b+1) = 18. Since a3    a+14a \ge 3 \implies a+1 \ge 4, possible integer pairs for (a+1,b+1)(a+1, b+1) are (6,3)(6, 3) giving a=5,b=2    a+b+c=8a=5, b=2 \implies a+b+c = 8, or (9,2)(9, 2) giving a=8,b=1    a+b+c=10a=8, b=1 \implies a+b+c = 10.
If c=2c = 2, then c+1=3c+1 = 3, so (a+1)(b+1)=12(a+1)(b+1) = 12. With a+14a+1 \ge 4, possible pairs for (a+1,b+1)(a+1, b+1) are (4,3)(4, 3) giving a=3,b=2    a+b+c=3+2+2=7a=3, b=2 \implies a+b+c = 3+2+2 = 7, or (6,2)(6, 2) giving a=5,b=1    a+b+c=8a=5, b=1 \implies a+b+c = 8.
Test allowable values of cc to find all valid exponent triples (a,b,c)(a, b, c) and minimize their sum.
4
Identify the minimum sum
The minimum sum of a+b+ca + b + c is 77, achieved when a=3a = 3, b=2b = 2, and c=2c = 2.
Compare sums across all valid exponent combinations.

Anahtar Kavram

Prime Factorization, Divisibility Rules, and Number of Divisors Formula
Tahmini Süre:2m 0s
Soru 124Soru

On the real number line, xx is a real number such that x+25|x + 2| \le 5. Which of the following could be the value of xx? Select all such values.

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Cevap: 7-7; 00; 33

Cevap

The values that satisfy the inequality are 7-7, 00, and 33.
The inequality x+25|x + 2| \le 5 represents all real numbers xx whose distance from 2-2 on the number line is at most 55. This gives the closed interval [7,3][-7, 3]. The values 7-7, 00, and 33 all fall within this range.

Adım Adım Çözüm

1
Set up the compound inequality for the absolute value expression.
5x+25-5 \le x + 2 \le 5
For any real number expression AA and non-negative constant kk, Ak|A| \le k is equivalent to kAk-k \le A \le k.
2
Isolate xx by subtracting 22 from all parts of the inequality.
52x52    7x3-5 - 2 \le x \le 5 - 2 \implies -7 \le x \le 3
Subtracting a constant from all parts preserves the inequality signs.
3
Evaluate which given choices lie within the interval [7,3][-7, 3].
7-7, 00, and 33 lie within [7,3][-7, 3], while 8-8 and 44 lie outside.
Only values inside or on the boundaries of [7,3][-7, 3] satisfy the inequality.

Anahtar Kavram

Absolute Value Inequalities and Real Number Line Distance
Soru 125Soru

Let aa and bb be positive integers such that 15a=28b15a = 28b. Which of the following statements MUST be true? Select all that apply.

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Cevap: aa is divisible by 77; bb is divisible by 1515

Cevap

The statements asserting that aa is divisible by 77 and that bb is divisible by 1515 must be true.
Equating prime factorizations gives (35)a=(227)b(3 \cdot 5) \cdot a = (2^2 \cdot 7) \cdot b. Because 1515 and 2828 share no common prime factors, aa must contain 227=282^2 \cdot 7 = 28 as a factor, and bb must contain 35=153 \cdot 5 = 15 as a factor. Therefore, aa is divisible by 77 (since 77 divides 2828) and bb is divisible by 1515.

Adım Adım Çözüm

1
Analyze the prime factorization of both sides of the equation.
The given equation 15a=28b15a = 28b can be rewritten as (35)a=(227)b(3 \cdot 5) \cdot a = (2^2 \cdot 7) \cdot b.
Prime factorizations allow us to identify fundamental divisibility relationships between variables.
2
Determine the prime factors required for aa and bb.
aa must be divisible by 2828 (i.e., a=28ka = 28k for some integer k1k \ge 1), and bb must be divisible by 1515 (i.e., b=15kb = 15k for the same integer kk).
Since gcd(15,28)=1\gcd(15, 28) = 1, all prime factors of 2828 (222^2 and 77) must come from aa, and all prime factors of 1515 (33 and 55) must come from bb.
3
Evaluate each choice against these general forms.
Since a=28ka = 28k, aa is a multiple of 77, making the first statement true. Since b=15kb = 15k, bb is a multiple of 1515, making the second statement true.
Any factor of 2828 is automatically a factor of aa, and any factor of 1515 is automatically a factor of bb.

Anahtar Kavram

Fundamental Theorem of Arithmetic and Coprime Divisibility Rules
Soru 126Soru

An agricultural research station divides an experimental plot of land among three crops: Wheat, Rye, and Barley. Initially, Wheat occupies 49\frac{4}{9} of the total plot area, Rye occupies 13\frac{1}{3} of the total area, and Barley occupies the remaining area. First, 13\frac{1}{3} of the Wheat area is converted to Rye. Next, 25\frac{2}{5} of the new total Rye area is converted to Barley. Finally, 14\frac{1}{4} of the new total Barley area is converted back to Wheat. If the final area occupied by Wheat is 126126 hectares, what was the total area, in hectares, of the experimental plot?

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Cevap: 315

Cevap

315 hectares
By tracking the dynamic changes to each crop's area step-by-step, the final Wheat area is 54135=25\frac{54}{135} = \frac{2}{5} of the total land area. Setting 25T=126\frac{2}{5} T = 126 yields T=315T = 315 hectares.

Adım Adım Çözüm

1
Determine initial fraction allocations for each crop
Wheat: 49\frac{4}{9}, Rye: 13=39\frac{1}{3} = \frac{3}{9}, Barley: 1(49+39)=291 - \left(\frac{4}{9} + \frac{3}{9}\right) = \frac{2}{9}
The sum of all three crop areas must equal the total area (11).
2
Apply the first conversion (13\frac{1}{3} of Wheat area converted to Rye)
Wheat transferred: 13×49=427\frac{1}{3} \times \frac{4}{9} = \frac{4}{27}. New Wheat: 49427=827\frac{4}{9} - \frac{4}{27} = \frac{8}{27}. New Rye: 13+427=1327\frac{1}{3} + \frac{4}{27} = \frac{13}{27}. Barley: 29=627\frac{2}{9} = \frac{6}{27}.
Wheat loses 13\frac{1}{3} of its current area, and Rye gains that exact amount.
3
Apply the second conversion (25\frac{2}{5} of new Rye area converted to Barley)
Rye transferred: 25×1327=26135\frac{2}{5} \times \frac{13}{27} = \frac{26}{135}. New Rye: 132726135=39135\frac{13}{27} - \frac{26}{135} = \frac{39}{135}. New Barley: 627+26135=56135\frac{6}{27} + \frac{26}{135} = \frac{56}{135}. Wheat remains 827=40135\frac{8}{27} = \frac{40}{135}.
Rye loses 25\frac{2}{5} of its updated area, and Barley gains that exact amount.
4
Apply the third conversion (14\frac{1}{4} of new Barley area converted to Wheat)
Barley transferred: 14×56135=14135\frac{1}{4} \times \frac{56}{135} = \frac{14}{135}. New Wheat: 40135+14135=54135=25\frac{40}{135} + \frac{14}{135} = \frac{54}{135} = \frac{2}{5}.
Barley loses 14\frac{1}{4} of its updated area, and Wheat gains that exact amount.
5
Solve for the total plot area TT
25T=126    T=126×52=315\frac{2}{5} T = 126 \implies T = \frac{126 \times 5}{2} = 315 hectares.
Set the final calculated fraction of Wheat equal to the given area of 126126 hectares.

Anahtar Kavram

Sequential fractional updates of non-disjoint sub-amounts
Tahmini Süre:2m 30s
Soru 127Soru

An investor divides a total initial investment of $10,000\$10,000 between Account XX and Account YY. Account XX earns simple annual interest at a rate of 6%6\%, while Account YY earns annual interest at a rate of 10%10\% compounded annually. If no additional deposits or withdrawals are made and the total interest earned from both accounts combined at the end of 22 years is $1,560\$1,560, how much money was originally invested in Account YY?

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Cevap: $4,000\$4,000

Cevap

$4,000\$4,000
The correct answer of $4,000\$4,000 is determined by calculating the interest earned by each account over two years. Account X earns simple interest of 6%×2=12%6\% \times 2 = 12\%, producing interest equal to 0.12(10,000PY)0.12(10,000 - P_Y). Account Y earns compound interest at 10%10\% annually, yielding an interest factor of 1.1021=0.211.10^2 - 1 = 0.21, or 0.21PY0.21 P_Y. Adding the interest expressions yields 1,200+0.09PY=1,5601,200 + 0.09 P_Y = 1,560, which simplifies to 0.09PY=3600.09 P_Y = 360 and gives PY=$4,000P_Y = \$4,000.

Adım Adım Çözüm

1
Define variables for the initial principal in each account
Let PYP_Y be the principal in Account YY. Then the principal in Account XX is 10,000PY10,000 - P_Y.
The total investment across both accounts is $10,000\$10,000.
2
Calculate the interest earned by Account XX over 22 years
\text{Interest}_X = (10,000 - P_Y) \times 0.06 \times 2 = 0.12(10,000 - P_Y) = 1,200 - 0.12 P_Y.
Account XX earns simple annual interest of 6%6\% per year for 22 years.
3
Calculate the interest earned by Account YY over 22 years
\text{Interest}_Y = P_Y \times ((1 + 0.10)^2 - 1) = P_Y \times (1.21 - 1) = 0.21 P_Y.
Account YY earns interest compounded annually at 10%10\% per year for 22 years.
4
Formulate and solve the equation for total interest
(1,200 - 0.12 P_Y) + 0.21 P_Y = 1,560 \implies 1,200 + 0.09 P_Y = 1,560 \implies 0.09 P_Y = 360 \implies P_Y = 4,000.
The combined interest from both accounts equals $1,560\$1,560.

Anahtar Kavram

Simple vs Compound Interest over multiple time periods
Soru 128Soru

Let mm and nn be positive integers whose prime factorizations consist only of the prime factors 22, 33, and 55. The greatest common divisor of mm and nn is 360360, and their least common multiple is 108,000108,000. If the power of 22 in the prime factorization of mm is strictly greater than the power of 22 in the prime factorization of nn, and mm has exactly 3636 positive divisors, what is the total number of positive divisors of nn?

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Cevap: 6464

Cevap

The total number of positive divisors of nn is 6464.
By writing the GCD and LCM in prime factorized form, GCD(m,n)=23×32×51\text{GCD}(m,n) = 2^3 \times 3^2 \times 5^1 and LCM(m,n)=25×33×53\text{LCM}(m,n) = 2^5 \times 3^3 \times 5^3. Given a>xa > x for the exponent of 22, we obtain a=5a=5 and x=3x=3. Using the divisor count formula for mm, 6(b+1)(c+1)=366(b+1)(c+1) = 36, which requires (b+1)(c+1)=6(b+1)(c+1) = 6. Testing possible exponent values b{2,3}b \in \{2,3\} reveals that only b=2b=2 yields an integer exponent c=1c=1. This uniquely determines n=23×33×53n = 2^3 \times 3^3 \times 5^3. Calculating (3+1)(3+1)(3+1)(3+1)(3+1)(3+1) gives 6464 positive divisors.

Adım Adım Çözüm

1
Express the greatest common divisor (GCD) and least common multiple (LCM) in prime factorization form.
GCD(m,n)=360=23×32×51\text{GCD}(m, n) = 360 = 2^3 \times 3^2 \times 5^1 and LCM(m,n)=108,000=25×33×53\text{LCM}(m, n) = 108,000 = 2^5 \times 3^3 \times 5^3.
Prime factorizations allow direct comparison of the minimum and maximum exponents for each prime factor.
2
Determine the exponent of 22 for both integers.
For prime factor 22, min(a,x)=3\min(a, x) = 3 and max(a,x)=5\max(a, x) = 5. Since the exponent of 22 in mm is strictly greater than in nn (a>xa > x), a=5a = 5 and x=3x = 3.
The GCD gives the lower exponent bound while the LCM gives the upper exponent bound.
3
Use the number of divisors of mm to solve for its remaining exponents.
Let m=25×3b×5cm = 2^5 \times 3^b \times 5^c. The number of positive divisors of mm is (5+1)(b+1)(c+1)=6(b+1)(c+1)=36(5+1)(b+1)(c+1) = 6(b+1)(c+1) = 36, so (b+1)(c+1)=6(b+1)(c+1) = 6. Since b{2,3}b \in \{2, 3\}, if b=3b = 3 then b+1=4b+1=4 which does not divide 66. Thus, b=2b = 2 and c=1c = 1.
The divisor count formula requires integer exponents, uniquely identifying b=2b = 2 and c=1c = 1 for mm.
4
Determine the exponents for nn and calculate its divisor count.
Since b=2b = 2 and max(b,y)=3\max(b, y) = 3, y=3y = 3. Since c=1c = 1 and max(c,z)=3\max(c, z) = 3, z=3z = 3. Thus n=23×33×53n = 2^3 \times 3^3 \times 5^3, and its divisor count is (3+1)(3+1)(3+1)=64(3+1)(3+1)(3+1) = 64.
Combining the max/min constraints from LCM/GCD yields all exponents of nn.

Anahtar Kavram

GCD and LCM Prime Exponent Relations & Divisor Counting Formula
Tahmini Süre:3m 0s
Soru 129Soru

The market value of a rare piece of artwork increased by x%x\% during its first decade in a gallery and then decreased by x%x\% during its second decade. If the artwork's market value at the end of the second decade was $19,200\$19,200, which represented a net decrease of $800\$800 from its initial market value prior to the two decades, what is the value of xx?

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Cevap: 2020

Cevap

The value of xx is 2020.
The initial value of the artwork is $19,200+$800=$20,000\$19,200 + \$800 = \$20,000. Applying an increase of x%x\% followed by a decrease of x%x\% gives a net value of $20,000×(1+x100)(1x100)=$20,000(1x210,000)\$20,000 \times (1 + \frac{x}{100})(1 - \frac{x}{100}) = \$20,000 \left(1 - \frac{x^2}{10,000}\right). Setting this equal to $19,200\$19,200 yields 1x210,000=0.961 - \frac{x^2}{10,000} = 0.96, which simplifies to x210,000=0.04\frac{x^2}{10,000} = 0.04, so x2=400x^2 = 400 and x=20x = 20.

Adım Adım Çözüm

1
Determine the initial market value before the two decades.
Initial Value =$19,200+$800=$20,000= \$19,200 + \$800 = \$20,000.
The final value of $19,200\$19,200 reflects a net decrease of $800\$800 from the original starting value.
2
Express the successive percentage changes in terms of xx.
Final Value =Initial Value×(1+x100)×(1x100)=Initial Value×(1x210,000)= \text{Initial Value} \times \left(1 + \frac{x}{100}\right) \times \left(1 - \frac{x}{100}\right) = \text{Initial Value} \times \left(1 - \frac{x^2}{10,000}\right).
An increase of x%x\% followed by a decrease of x%x\% on the new base yields the difference of squares formula for percent multipliers.
3
Set up the equation with known numerical values and solve for x2x^2.
20,000(1x210,000)=19,200    1x210,000=19,20020,000=0.96    x210,000=0.04    x2=40020,000 \left(1 - \frac{x^2}{10,000}\right) = 19,200 \implies 1 - \frac{x^2}{10,000} = \frac{19,200}{20,000} = 0.96 \implies \frac{x^2}{10,000} = 0.04 \implies x^2 = 400.
Dividing the final value by the initial value gives the net multiplier of 0.960.96, meaning a 4%4\% overall decrease.
4
Take the positive square root to find xx.
x=400=20x = \sqrt{400} = 20.
Since xx represents a positive percentage rate, x=20x = 20.

Anahtar Kavram

Successive percentage changes and base shifts using the difference of squares (1+k)(1k)=1k2(1 + k)(1 - k) = 1 - k^2.
Tahmini Süre:2m 0s
Soru 130Soru

At the beginning of 2025, Company X's allocation for Marketing was 40%40\% greater than its allocation for Research. Over the course of the year, the Marketing allocation was decreased by 25%25\%, while the Research allocation was increased by p%p\%. At the end of 2025, the revised Research allocation was 20%20\% greater than the revised Marketing allocation. What is the value of pp?

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Cevap: 26

Cevap

The value of pp is 26.
The correct option correctly applies successive percentage changes to each variable. Starting with Research as RR, Marketing is 1.40R1.40R. Reducing Marketing by 25%25\% yields 1.40R×0.75=1.05R1.40R \times 0.75 = 1.05R. Increasing this result by 20%20\% gives the final Research amount of 1.20×1.05R=1.26R1.20 \times 1.05R = 1.26R, corresponding to a 26%26\% increase over the initial Research allocation RR.

Adım Adım Çözüm

1
Define variables for the initial allocations of both departments.
Let RR represent the initial Research allocation. Then the initial Marketing allocation is 1.40R1.40R.
Marketing was 40%40\% greater than Research at the start of the year.
2
Calculate the revised Marketing allocation at the end of the year.
Revised Marketing allocation =1.40R×(10.25)=1.40R×0.75=1.05R= 1.40R \times (1 - 0.25) = 1.40R \times 0.75 = 1.05R.
The Marketing allocation decreased by 25%25\% from its initial value.
3
Determine the revised Research allocation using the end-of-year relationship.
Revised Research allocation =1.20×1.05R=1.26R= 1.20 \times 1.05R = 1.26R.
The revised Research allocation was 20%20\% greater than the revised Marketing allocation.
4
Find the percentage increase pp for the Research allocation.
R(1+p100)=1.26R    1+p100=1.26    p=26R \left(1 + \frac{p}{100}\right) = 1.26R \implies 1 + \frac{p}{100} = 1.26 \implies p = 26.
The change from RR to 1.26R1.26R represents a 26%26\% increase.

Anahtar Kavram

Successive percent changes and base shifts in multi-variable algebraic scenarios
Tahmini Süre:2m 30s
Soru 131Soru

On a number line, point PP corresponds to 3-3 and point QQ corresponds to 55. If point RR is the midpoint of line segment PQPQ, what is the value of RP|R - P|?

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Cevap: 44

Cevap

The correct distance between point P and midpoint R is 4.
The total distance between P(3)P (-3) and Q(5)Q (5) on the real number line is 5(3)=8|5 - (-3)| = 8. Since RR is the midpoint of segment PQPQ, it splits the total length into two equal halves of length 44. Therefore, the distance from PP to RR, represented by RP|R - P|, is 44.

Adım Adım Çözüm

1
Calculate the total distance between points P and Q on the number line.
Distance PQ=5(3)=5+3=8PQ = |5 - (-3)| = |5 + 3| = 8.
The distance between any two points aa and bb on a number line is given by ba|b - a|.
2
Find the coordinate of the midpoint R.
Coordinate of R=3+52=22=1R = \frac{-3 + 5}{2} = \frac{2}{2} = 1.
The midpoint coordinate is the average of the coordinates of the two endpoints.
3
Calculate the absolute distance between R and P.
RP=1(3)=1+3=4|R - P| = |1 - (-3)| = |1 + 3| = 4.
The absolute value gives the non-negative distance between the midpoint and point P.

Anahtar Kavram

Distance on a Number Line and Midpoint Formula
Soru 132Soru

Let M=3.2×105M = 3.2 \times 10^{-5} and N=8.0×104N = 8.0 \times 10^{-4}. Which of the following statements must be true? Select all that apply.

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Cevap: NM=7.68×104N - M = 7.68 \times 10^{-4}; The ratio NM\frac{N}{M} is equal to 2525; 1M=3.125×104\frac{1}{M} = 3.125 \times 10^4

Cevap

The correct statements are NM=7.68×104N - M = 7.68 \times 10^{-4}, the ratio NM\frac{N}{M} is equal to 2525, and 1M=3.125×104\frac{1}{M} = 3.125 \times 10^4.
The statement NM=7.68×104N - M = 7.68 \times 10^{-4} is true because expressing both numbers with the exponent 10410^{-4} gives (8.00.32)×104=7.68×104(8.0 - 0.32) \times 10^{-4} = 7.68 \times 10^{-4}. The statement that the ratio NM\frac{N}{M} is equal to 2525 is true because 8.03.2×104(5)=2.5×10=25\frac{8.0}{3.2} \times 10^{-4 - (-5)} = 2.5 \times 10 = 25. The statement 1M=3.125×104\frac{1}{M} = 3.125 \times 10^4 is true because 13.2×105=0.3125×105=3.125×104\frac{1}{3.2} \times 10^5 = 0.3125 \times 10^5 = 3.125 \times 10^4.

Adım Adım Çözüm

1
Evaluate NMN - M
NM=7.68×104N - M = 7.68 \times 10^{-4}
Convert MM to the exponent 10410^{-4}: M=0.32×104M = 0.32 \times 10^{-4}. Then NM=(8.00.32)×104=7.68×104N - M = (8.0 - 0.32) \times 10^{-4} = 7.68 \times 10^{-4}.
2
Evaluate NM\frac{N}{M}
NM=25\frac{N}{M} = 25
Divide coefficients and subtract exponents: 8.03.2×104(5)=2.5×101=25\frac{8.0}{3.2} \times 10^{-4 - (-5)} = 2.5 \times 10^1 = 25.
3
Evaluate MN\sqrt{M \cdot N}
\sqrt{M \cdot N} = 1.6 \times 10^{-4}
Compute MN=25.6×109=2.56×108M \cdot N = 25.6 \times 10^{-9} = 2.56 \times 10^{-8}. Take the square root: 2.56×108=1.6×104\sqrt{2.56} \times \sqrt{10^{-8}} = 1.6 \times 10^{-4}.
4
Evaluate M+NM + N
M+N=8.32×104M + N = 8.32 \times 10^{-4}
Express with common powers of ten: 0.32×104+8.0×104=8.32×1040.32 \times 10^{-4} + 8.0 \times 10^{-4} = 8.32 \times 10^{-4}.
5
Evaluate 1M\frac{1}{M}
1M=3.125×104\frac{1}{M} = 3.125 \times 10^4
Compute 13.2×105=0.3125×105=3.125×104\frac{1}{3.2 \times 10^{-5}} = 0.3125 \times 10^5 = 3.125 \times 10^4.

Anahtar Kavram

Operations with numbers in scientific notation and place value adjustments
Soru 133Soru

At a financial trading firm, incoming trade orders pass through a three-stage automated verification pipeline:

1. In Stage 1, 16\frac{1}{6} of all incoming orders are rejected as invalid, and 15\frac{1}{5} of the remaining valid orders are flagged for manual review.
2. In Stage 2, of the orders that were cleared directly without manual review, 38\frac{3}{8} are executed immediately, while the rest are placed in a waiting queue.
3. In Stage 3, 13\frac{1}{3} of the queued orders are processed, leaving the remaining queued orders unprocessed.

If exactly 250250 queued orders remain unprocessed at the end of Stage 3, how many incoming orders were flagged for manual review in Stage 1?

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Cevap: 150

Cevap

150 orders were flagged for manual review in Stage 1.
Let NN represent the total number of incoming trade orders. In Stage 1, after 16N\frac{1}{6}N orders are rejected, 56N\frac{5}{6}N remain. Flagging 15\frac{1}{5} of these remaining valid orders means 15×56N=16N\frac{1}{5} \times \frac{5}{6}N = \frac{1}{6}N orders are flagged for manual review, leaving 56N16N=23N\frac{5}{6}N - \frac{1}{6}N = \frac{2}{3}N orders cleared directly. In Stage 2, 58\frac{5}{8} of the cleared orders enter the queue, which equals 58×23N=512N\frac{5}{8} \times \frac{2}{3}N = \frac{5}{12}N. In Stage 3, 23\frac{2}{3} of the queued orders remain unprocessed, giving 23×512N=518N\frac{2}{3} \times \frac{5}{12}N = \frac{5}{18}N. Setting 518N=250\frac{5}{18}N = 250 yields N=900N = 900. The number of orders flagged for manual review is 16×900=150\frac{1}{6} \times 900 = 150.

Adım Adım Çözüm

1
Determine the fraction of orders cleared directly in Stage 1.
The fraction of valid orders remaining after rejection is 116=561 - \frac{1}{6} = \frac{5}{6}. The fraction flagged for manual review is 15×56=16\frac{1}{5} \times \frac{5}{6} = \frac{1}{6} of the total. Thus, the fraction cleared directly is 5616=46=23\frac{5}{6} - \frac{1}{6} = \frac{4}{6} = \frac{2}{3} of total incoming orders.
Sequential fractional deductions must be applied to the remaining amounts at each sub-stage.
2
Determine the fraction of orders placed in the queue during Stage 2.
Of the 23\frac{2}{3} directly cleared orders, 38\frac{3}{8} are executed immediately, so 138=581 - \frac{3}{8} = \frac{5}{8} are placed in the queue. The fraction of total incoming orders queued is 58×23=512\frac{5}{8} \times \frac{2}{3} = \frac{5}{12}.
Fraction of a fraction requires multiplying the operational fraction by the current subtotal.
3
Determine the fraction of total incoming orders that remain unprocessed at the end of Stage 3.
Since 13\frac{1}{3} of queued orders are processed, 113=231 - \frac{1}{3} = \frac{2}{3} of the queued orders remain unprocessed. The fraction of total orders unprocessed is 23×512=518\frac{2}{3} \times \frac{5}{12} = \frac{5}{18}.
Multiply the remaining fraction in Stage 3 by the total queued fraction from Stage 2.
4
Calculate the total number of incoming orders (NN) and the target flagged orders.
Setting 518N=250\frac{5}{18}N = 250 gives N=250×185=900N = 250 \times \frac{18}{5} = 900 total incoming orders. The number of orders flagged for manual review is 16×900=150\frac{1}{6} \times 900 = 150.
Equate the given numerical quantity to its fractional equivalent to find the total, then compute the required part.

Anahtar Kavram

Multi-step fraction calculations involving fractions of remaining quantities and working backward from a known part to the whole.
Soru 134Soru

A boutique owner increases the original price of a handbag by 25%25\%. One month later, the owner reduces the updated price by 20%20\%. Which of the following statements about the price of the handbag must be true? Select all such statements.

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Cevap: The final price of the handbag is equal to its original price.; The overall net percent change in the price of the handbag is 0%0\%.; The dollar amount of the 25%25\% increase is equal to the dollar amount of the 20%20\% discount.

Cevap

The correct statements are: the final price is equal to the original price, the overall net percent change is 0%, and the dollar amount of the 25% increase equals the dollar amount of the 20% discount.
Applying a 25% increase to an initial amount PP yields 1.25P1.25P, representing a 0.25P0.25P increase. Taking 20% off of 1.25P1.25P calculates to 0.20×1.25P=0.25P0.20 \times 1.25P = 0.25P. Subtracting 0.25P0.25P from 1.25P1.25P returns the price to 1.00P1.00P. Therefore, the final price is equal to the original price, the overall percent change is 0%, and the two dollar changes are equal.

Adım Adım Çözüm

1
Define a variable for the original price and calculate the price after the 25% increase.
Let the original price be PP. The price after a 25%25\% increase is P+0.25P=1.25PP + 0.25P = 1.25P. The dollar increase is 0.25P0.25P.
Establishing the intermediate price is necessary to apply the subsequent discount correctly.
2
Calculate the price after the 20% discount applied to the updated price.
The discount amount is 20%20\% of 1.25P1.25P, which is 0.20×1.25P=0.25P0.20 \times 1.25P = 0.25P. The final price is 1.25P0.25P=1.00P1.25P - 0.25P = 1.00P.
Percentage discounts must be evaluated using the price immediately preceding the discount as the base value.
3
Evaluate the net change and compare dollar amounts.
Final price = Original price (PP). Net percent change = 1.00PPP×100%=0%\frac{1.00P - P}{P} \times 100\% = 0\%. Dollar increase (0.25P0.25P) = Dollar decrease (0.25P0.25P).
Comparing final values to initial values confirms which statements are true.

Anahtar Kavram

Successive Percentage Changes and Base Value Shifts
Soru 135Soru

On Monday, a community kitchen starts with a bulk container of rice. First, 13\frac{1}{3} of the initial supply of rice is used for lunch. Next, 14\frac{1}{4} of the remaining rice in the container is used for dinner. After preparing both meals, exactly 6060 kilograms of rice remain in the container. How many kilograms of rice were in the container initially?

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Cevap: 120 kg

Cevap

120 kg
The correct option is 120 kg. After using 13\frac{1}{3} of the initial supply for lunch, 23\frac{2}{3} of the supply remains. Using 14\frac{1}{4} of this remaining amount for dinner leaves 34\frac{3}{4} of the 23\frac{2}{3} remaining. Multiplying these fractions gives 34×23=12\frac{3}{4} \times \frac{2}{3} = \frac{1}{2} of the original supply. Since 12\frac{1}{2} of the original supply equals 6060 kg, the initial total supply was 60×2=12060 \times 2 = 120 kg.

Adım Adım Çözüm

1
Determine the fraction of rice remaining after lunch.
Since 13\frac{1}{3} of the initial supply is used for lunch, 113=231 - \frac{1}{3} = \frac{2}{3} of the initial supply remains.
The remaining portion after lunch is the base for the next fractional reduction.
2
Determine the fraction of rice used for dinner and the fraction remaining overall.
Dinner uses 14\frac{1}{4} of the remaining 23\frac{2}{3}, which is 14×23=16\frac{1}{4} \times \frac{2}{3} = \frac{1}{6} of the initial total supply. The total fraction used is 13+16=12\frac{1}{3} + \frac{1}{6} = \frac{1}{2}. Thus, the fraction remaining after dinner is 112=121 - \frac{1}{2} = \frac{1}{2} of the initial total.
Sequential fractional reductions require multiplying the second fraction by the remaining fraction from the first step.
3
Solve for the initial total mass of rice.
Let RR be the initial mass in kilograms. Then 12R=60    R=120\frac{1}{2} R = 60 \implies R = 120 kg.
Setting the calculated remaining fraction equal to the given numerical remaining quantity yields the starting total.

Anahtar Kavram

Sequential Fraction of Remaining Quantities
Tahmini Süre:1m 30s
Soru 136Soru

Let NN be a positive integer with exactly 1212 positive divisors. If the sum of the distinct prime factors of NN is 1212 and NN is not divisible by 44, what is the least possible value of NN?

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Cevap: 126

Cevap

126
The least possible value of NN is 126. The only sets of distinct prime factors summing to 12 are {5,7}\{5, 7\} and {2,3,7}\{2, 3, 7\}. Using {2,3,7}\{2, 3, 7\} produces smaller candidates. Because NN is not divisible by 4, the exponent of 2 must be 1. The total divisor condition (1+1)(b+1)(c+1)=12(1+1)(b+1)(c+1) = 12 requires (b+1)(c+1)=6(b+1)(c+1) = 6, giving exponent pairs (1,2)(1, 2) or (2,1)(2, 1) for bases 3 and 7. Assigning the exponent 2 to 3 and 1 to 7 minimizes NN, giving 213271=1262^1 \cdot 3^2 \cdot 7^1 = 126.

Adım Adım Çözüm

1
Find all sets of distinct prime factors that sum to 12.
The possible sets of distinct prime factors are {5,7}\{5, 7\} and {2,3,7}\{2, 3, 7\}.
Testing combinations of prime numbers (2,3,5,7,11,2, 3, 5, 7, 11, \dots): 5+7=125 + 7 = 12 and 2+3+7=122 + 3 + 7 = 12 are the only valid sets of distinct primes summing to 12.
2
Analyze the set of prime factors {2,3,7}\{2, 3, 7\} under the condition that NN is not divisible by 4.
The prime factorization is N=2a3b7cN = 2^a \cdot 3^b \cdot 7^c, where a=1a = 1.
Since 2 is a prime factor of NN, a1a \ge 1. Because NN is not divisible by 4 (222^2), aa must be strictly less than 2. Thus, a=1a = 1.
3
Determine the exponents bb and cc using the total number of positive divisors.
The number of divisors is (1+1)(b+1)(c+1)=12(1+1)(b+1)(c+1) = 12, which simplifies to (b+1)(c+1)=6(b+1)(c+1) = 6. The possible integer pairs (b,c)(b, c) for b,c1b, c \ge 1 are (1,2)(1, 2) and (2,1)(2, 1).
The divisor count formula for N=p1e1p2e2pkekN = p_1^{e_1} p_2^{e_2} \dots p_k^{e_k} is (e1+1)(e2+1)(ek+1)=12(e_1+1)(e_2+1)\dots(e_k+1) = 12.
4
Calculate values of NN for these exponent pairs.
For (b,c)=(1,2)(b, c) = (1, 2), N=213172=294N = 2^1 \cdot 3^1 \cdot 7^2 = 294. For (b,c)=(2,1)(b, c) = (2, 1), N=213271=126N = 2^1 \cdot 3^2 \cdot 7^1 = 126.
To make NN as small as possible, assign the larger exponent to the smaller prime base (3271<31723^2 \cdot 7^1 < 3^1 \cdot 7^2).
5
Compare with candidate values from the alternative set of prime factors {5,7}\{5, 7\}.
For {5,7}\{5, 7\}, N=5372=6125N = 5^3 \cdot 7^2 = 6125 or 5571=218755^5 \cdot 7^1 = 21875, both of which are much larger than 126.
The combination (a+1)(b+1)=12(a+1)(b+1) = 12 yields exponents of 3 and 2 (or 5 and 1), resulting in much higher prime powers.

Anahtar Kavram

Divisor count formula combined with prime factorization constraints
Soru 137Soru

A residential solar power system generated 40004{}000 kilowatt-hours (kWh\text{kWh}) of electricity during its first year of operation. In the second year, electricity generation decreased by 10%10\%. In the third year, electricity generation increased by 10%10\% relative to the second year's generation. How many kilowatt-hours of electricity did the solar system generate in the third year?

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Cevap: 39603{}960

Cevap

The solar power system generated 3960 kWh3{}960\text{ kWh} of electricity in the third year.
In the first year, generation was 4000 kWh4{}000\text{ kWh}. A 10%10\% decrease yields 4000×(10.10)=3600 kWh4{}000 \times (1 - 0.10) = 3{}600\text{ kWh} for the second year. In the third year, a 10%10\% increase over the second year's generation yields 3600×(1+0.10)=3960 kWh3{}600 \times (1 + 0.10) = 3{}960\text{ kWh}.

Adım Adım Çözüm

1
Calculate the electricity generated in the second year after a 10%10\% decrease from the first year.
4000(0.10×4000)=4000400=3600 kWh4{}000 - (0.10 \times 4{}000) = 4{}000 - 400 = 3{}600\text{ kWh}
A 10%10\% decrease means retaining 90%90\% of the original 4000 kWh4{}000\text{ kWh} base.
2
Calculate the electricity generated in the third year after a 10%10\% increase over the second year's total.
3600+(0.10×3600)=3600+360=3960 kWh3{}600 + (0.10 \times 3{}600) = 3{}600 + 360 = 3{}960\text{ kWh}
The 10%10\% increase applies to the new base value of 3600 kWh3{}600\text{ kWh}, not the initial 4000 kWh4{}000\text{ kWh}.

Anahtar Kavram

Successive Percent Changes and Base Shifts
Tahmini Süre:45s
Soru 138Soru

If xx is a positive integer such that 120120 is a factor of x2x^2, what is the least possible value of xx?

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Cevap: 60

Cevap

60
The prime factorization of 120 is 23×31×512^3 \times 3^1 \times 5^1. For x2x^2 to be divisible by 120, x2x^2 must contain at least three 2s, one 3, and one 5. Because x2x^2 is a perfect square, all exponents in its prime factorization must be even numbers. Thus, the minimum prime factorization for x2x^2 is 24×32×522^4 \times 3^2 \times 5^2, which means xx must be at least 22×31×51=602^2 \times 3^1 \times 5^1 = 60.

Adım Adım Çözüm

1
Find the prime factorization of 120.
120=23×31×51120 = 2^3 \times 3^1 \times 5^1
Decomposing 120 into prime factors reveals the minimal prime factor exponents required for x2x^2.
2
Determine the prime factors required for x2x^2 to be divisible by 120.
The prime factorization of x2x^2 must contain even exponents for all its prime factors and must be divisible by 23×31×512^3 \times 3^1 \times 5^1. Therefore, x2x^2 must contain at least 24×32×522^4 \times 3^2 \times 5^2.
Because x2x^2 is a perfect square, every prime factor in its prime factorization must have an even exponent.
3
Calculate the minimum value of xx.
x=24×32×52=22×31×51=4×3×5=60x = \sqrt{2^4 \times 3^2 \times 5^2} = 2^2 \times 3^1 \times 5^1 = 4 \times 3 \times 5 = 60
Taking the square root of 24×32×522^4 \times 3^2 \times 5^2 gives the least positive integer xx satisfying the condition.

Anahtar Kavram

Prime Factorization and Perfect Squares
Soru 139Soru

At the start of a fiscal year, a venture capital fund divided its total investment capital between Asset Class XX and Asset Class YY. Over the course of the year, the value of Asset Class XX increased by 25%25\%, while the value of Asset Class YY decreased by 40%40\%. At the end of the year, the total value of the fund was exactly equal to its total value at the start of the year. Which of the following statements must be true? Select all that apply.

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Cevap: At the start of the year, the value of Asset Class XX was 60%60\% greater than the value of Asset Class YY.; At the end of the year, Asset Class XX represented more than 75%75\% of the total value of the fund.; The dollar amount by which Asset Class XX increased was equal to the dollar amount by which Asset Class YY decreased.

Cevap

The statements that must be true are: at the start of the year, the value of Asset Class X was 60% greater than the value of Asset Class Y; at the end of the year, Asset Class X represented more than 75% of the total value of the fund; and the dollar amount by which Asset Class X increased was equal to the dollar amount by which Asset Class Y decreased.
The problem establishes that 0.25X=0.40Y0.25X = 0.40Y, which yields X=1.60YX = 1.60Y. This confirms that at the start of the year, the value of Asset Class XX was 60%60\% greater than Asset Class YY. Furthermore, the final value of Asset Class XX becomes 2.00Y2.00Y out of a total final fund value of 2.60Y2.60Y, giving it a share of 101376.92%\frac{10}{13} \approx 76.92\%, which is strictly greater than 75%75\%. Finally, because the total portfolio value is unchanged, the exact dollar increase in Asset Class XX (0.25X0.25X) must balance the dollar decrease in Asset Class YY (0.40Y0.40Y).

Adım Adım Çözüm

1
Set up an equation using initial variables XX and YY for the two asset classes.
Initial total value = X+YX + Y. Final value of X=1.25XX = 1.25X, final value of Y=0.60YY = 0.60Y. Final total value = 1.25X+0.60Y1.25X + 0.60Y.
Percentage increases and decreases apply directly as multiplier factors to their respective initial base values.
2
Equate the initial and final total fund values to find the relationship between XX and YY.
1.25X+0.60Y=X+Y    0.25X=0.40Y    X=1.60Y1.25X + 0.60Y = X + Y \implies 0.25X = 0.40Y \implies X = 1.60Y.
The problem states the net total value of the fund remained unchanged over the year.
3
Evaluate the initial relationship between Asset Class XX and Asset Class YY.
Since X=1.60Y=(1+0.60)YX = 1.60Y = (1 + 0.60)Y, Asset Class XX was 60%60\% greater than Asset Class YY at the start of the year.
A multiplier of 1.601.60 corresponds to a 60%60\% increase over the base value YY.
4
Determine the initial and final percentage allocations of Asset Class XX relative to the total fund.
Initial share = 1.60Y2.60Y=81361.54%\frac{1.60Y}{2.60Y} = \frac{8}{13} \approx 61.54\%. Final share = 1.25(1.60Y)1.25(1.60Y)+0.60Y=2.00Y2.60Y=101376.92%\frac{1.25(1.60Y)}{1.25(1.60Y) + 0.60Y} = \frac{2.00Y}{2.60Y} = \frac{10}{13} \approx 76.92\%.
Evaluating part-to-whole fractions demonstrates that the final share of Asset Class XX (76.92%76.92\%) exceeds 75%75\%.
5
Analyze dollar change equality between the assets.
Dollar gain in X=0.25XX = 0.25X. Dollar loss in Y=0.40YY = 0.40Y. Since 0.25X=0.40Y0.25X = 0.40Y, the dollar gain in XX equals the dollar loss in YY.
Zero net change in total fund value guarantees that positive dollar changes cancel negative dollar changes exactly.

Anahtar Kavram

Weighted Percentage Changes and Base Value Shifting
Tahmini Süre:3m 0s
Soru 140Soru

A retail store tracks the price of a commercial oven across three consecutive quarters.

- In Quarter 1, the original price PP was increased by x%x\%.
- In Quarter 2, the price was decreased by x%x\% from its Quarter 1 price.
- In Quarter 3, the price was increased by 25%25\% from its Quarter 2 price.

If the price at the end of Quarter 3 is 20%20\% greater than the original price PP, which of the following statements must be true? Select all such statements.

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Cevap: The value of xx is 2020.; The price at the end of Quarter 2 was 4%4\% less than the original price PP.

Cevap

The statements holding that the value of xx is 2020 and that the price at the end of Quarter 2 was 4%4\% less than the original price PP are both true.
The statement showing x=20x = 20 is correct because solving the multi-stage percent equation 1.25P(1x210,000)=1.20P1.25 P (1 - \frac{x^2}{10,000}) = 1.20P yields x=20x = 20. The statement showing that the Quarter 2 price was 4%4\% less than PP is correct because P2=P(140010,000)=0.96PP_2 = P(1 - \frac{400}{10,000}) = 0.96P, which represents a 4%4\% reduction relative to PP.

Adım Adım Çözüm

1
Express the price after each quarter algebraically in terms of initial price PP and rate xx.
Quarter 1 price: P1=P(1+x100)P_1 = P\left(1 + \frac{x}{100}\right). Quarter 2 price: P2=P1(1x100)=P(1x210,000)P_2 = P_1\left(1 - \frac{x}{100}\right) = P\left(1 - \frac{x^2}{10,000}\right). Quarter 3 price: P3=1.25P2=1.25P(1x210,000)P_3 = 1.25 P_2 = 1.25 P\left(1 - \frac{x^2}{10,000}\right).
Successive percentage changes compound sequentially on updated base values.
2
Set the Quarter 3 price expression equal to 1.20P1.20P and solve for xx.
1.25P(1x210,000)=1.20P    1x210,000=1.201.25=0.96    x210,000=0.04    x2=400    x=201.25 P\left(1 - \frac{x^2}{10,000}\right) = 1.20 P \implies 1 - \frac{x^2}{10,000} = \frac{1.20}{1.25} = 0.96 \implies \frac{x^2}{10,000} = 0.04 \implies x^2 = 400 \implies x = 20.
A price 20%20\% greater than PP equals 1.20P1.20P.
3
Evaluate intermediate values to test each statement.
P1=1.20PP_1 = 1.20P, P2=0.96PP_2 = 0.96P. The Quarter 1 increase is 0.20P0.20P, while the Quarter 2 decrease is 0.20×1.20P=0.24P0.20 \times 1.20P = 0.24P.
Comparing exact calculated dollar and percentage values allows for direct validation of each option.

Anahtar Kavram

Successive Percentage Changes and Base Shift Dependencies
ÖncekiSayfa 7 / 16Sonraki