3 × (1/2 + 1/3) =
- A. 2,1/2
- B. 2,5/6
- C. 3,1/6
- D. 3,5/6
Correct Answer & Rationale
Correct Answer: A
To solve 3 × (1/2 + 1/3), first find a common denominator for the fractions 1/2 and 1/3, which is 6. This gives us (3/6 + 2/6) = 5/6. Multiplying by 3 results in 3 × (5/6) = 15/6, which simplifies to 2 1/2 (Option A). Option B (2 5/6) incorrectly adds an extra fraction. Option C (3 1/6) miscalculates the multiplication. Option D (3 5/6) also misinterprets the original problem, leading to an incorrect total. Thus, only Option A accurately represents the solution.
To solve 3 × (1/2 + 1/3), first find a common denominator for the fractions 1/2 and 1/3, which is 6. This gives us (3/6 + 2/6) = 5/6. Multiplying by 3 results in 3 × (5/6) = 15/6, which simplifies to 2 1/2 (Option A). Option B (2 5/6) incorrectly adds an extra fraction. Option C (3 1/6) miscalculates the multiplication. Option D (3 5/6) also misinterprets the original problem, leading to an incorrect total. Thus, only Option A accurately represents the solution.
Other Related Questions
John worked at a bookstore for two weeks. The second week he earned 20 percent more than he did the first week. If he earned $300 the second week, how much did he earn the first week?
- A. 240
- B. 250
- C. 280
- D. 380
Correct Answer & Rationale
Correct Answer: B
To determine John’s earnings for the first week, we know that his second week earnings were 20% more than the first week. If he earned $300 in the second week, we can calculate his first week earnings by setting up the equation: Let x be the first week’s earnings. Then, x + 0.2x = 300. This simplifies to 1.2x = 300. Dividing both sides by 1.2 gives x = 250. Option A ($240) is too low, as it would not result in a $300 second week. Option C ($280) would imply a second week earning of $336, which exceeds $300. Option D ($380) is also incorrect as it suggests a second week earning of $456. Thus, $250 is the only viable answer.
To determine John’s earnings for the first week, we know that his second week earnings were 20% more than the first week. If he earned $300 in the second week, we can calculate his first week earnings by setting up the equation: Let x be the first week’s earnings. Then, x + 0.2x = 300. This simplifies to 1.2x = 300. Dividing both sides by 1.2 gives x = 250. Option A ($240) is too low, as it would not result in a $300 second week. Option C ($280) would imply a second week earning of $336, which exceeds $300. Option D ($380) is also incorrect as it suggests a second week earning of $456. Thus, $250 is the only viable answer.
The large square above has area 1 and is divided into 25 squares of equal area. Which of the following represents the area of the shaded region?
- A. 0.8
- B. 0.16
- C. 0.24
- D. 0.32
Correct Answer & Rationale
Correct Answer: D
In a large square with an area of 1, each of the 25 smaller squares has an area of \( \frac{1}{25} = 0.04 \). To find the area of the shaded region, count the number of shaded squares. If there are 8 shaded squares, then the area of the shaded region is \( 8 \times 0.04 = 0.32 \). Option A (0.8) is incorrect as it exceeds the total area of the large square. Option B (0.16) represents 4 shaded squares, which is not consistent with the given information. Option C (0.24) suggests 6 shaded squares, which also does not match. Thus, the area of the shaded region is accurately represented by option D, 0.32.
In a large square with an area of 1, each of the 25 smaller squares has an area of \( \frac{1}{25} = 0.04 \). To find the area of the shaded region, count the number of shaded squares. If there are 8 shaded squares, then the area of the shaded region is \( 8 \times 0.04 = 0.32 \). Option A (0.8) is incorrect as it exceeds the total area of the large square. Option B (0.16) represents 4 shaded squares, which is not consistent with the given information. Option C (0.24) suggests 6 shaded squares, which also does not match. Thus, the area of the shaded region is accurately represented by option D, 0.32.
Sienna has four times as many DVDs as Teri. Robert has half as many DVDs as Teri. If Robert has 32 DVDs, how many DVDs does Sienna have?
- A. 4
- B. 16
- C. 64
- D. 256
Correct Answer & Rationale
Correct Answer: D
To determine how many DVDs Sienna has, start with Robert's count. Since Robert has 32 DVDs and he has half as many as Teri, Teri must have 64 DVDs (32 x 2). Sienna has four times as many DVDs as Teri, so she has 256 DVDs (64 x 4). Option A (4) is incorrect because it underestimates the number of DVDs based on Teri's count. Option B (16) is also incorrect, as it does not align with the calculations derived from Robert's DVDs. Option C (64) mistakenly represents Teri's count rather than Sienna's. Thus, the only valid option reflecting Sienna's total is 256.
To determine how many DVDs Sienna has, start with Robert's count. Since Robert has 32 DVDs and he has half as many as Teri, Teri must have 64 DVDs (32 x 2). Sienna has four times as many DVDs as Teri, so she has 256 DVDs (64 x 4). Option A (4) is incorrect because it underestimates the number of DVDs based on Teri's count. Option B (16) is also incorrect, as it does not align with the calculations derived from Robert's DVDs. Option C (64) mistakenly represents Teri's count rather than Sienna's. Thus, the only valid option reflecting Sienna's total is 256.
7.50 ÷ 0.125 =
- A. 60
- B. 6
- C. 0.6
- D. 1/6
Correct Answer & Rationale
Correct Answer: A
To solve 7.50 ÷ 0.125, it's helpful to convert the division into a more manageable form. Dividing by 0.125 is the same as multiplying by 8 (since 1 ÷ 0.125 = 8). Therefore, 7.50 × 8 equals 60, confirming option A as the right choice. Option B (6) is incorrect; it underestimates the quotient significantly. Option C (0.6) is also wrong, as it suggests a much smaller result than what is obtained. Lastly, option D (1/6) misrepresents the division entirely, implying a fractional outcome that does not align with the calculations.
To solve 7.50 ÷ 0.125, it's helpful to convert the division into a more manageable form. Dividing by 0.125 is the same as multiplying by 8 (since 1 ÷ 0.125 = 8). Therefore, 7.50 × 8 equals 60, confirming option A as the right choice. Option B (6) is incorrect; it underestimates the quotient significantly. Option C (0.6) is also wrong, as it suggests a much smaller result than what is obtained. Lastly, option D (1/6) misrepresents the division entirely, implying a fractional outcome that does not align with the calculations.