2,3/8 + 5,5/6 =
- A. 7,5/24
- B. 7,4/7
- C. 8,5/24
- D. 8,4/7
Correct Answer & Rationale
Correct Answer: C
To solve 2,3/8 + 5,5/6, first convert the mixed numbers into improper fractions. For 2,3/8, this becomes (2 * 8 + 3)/8 = 19/8. For 5,5/6, it is (5 * 6 + 5)/6 = 35/6. Next, find a common denominator, which is 24. Convert the fractions: 19/8 becomes 57/24, and 35/6 becomes 140/24. Adding these gives 197/24, which converts back to a mixed number as 8,5/24. Options A and B do not match this result. Option D, while close, inaccurately represents the fraction.
To solve 2,3/8 + 5,5/6, first convert the mixed numbers into improper fractions. For 2,3/8, this becomes (2 * 8 + 3)/8 = 19/8. For 5,5/6, it is (5 * 6 + 5)/6 = 35/6. Next, find a common denominator, which is 24. Convert the fractions: 19/8 becomes 57/24, and 35/6 becomes 140/24. Adding these gives 197/24, which converts back to a mixed number as 8,5/24. Options A and B do not match this result. Option D, while close, inaccurately represents the fraction.
Other Related Questions
165 is what percent of 150?
- A. 95%
- B. 110%
- C. 111%
- D. 115%
Correct Answer & Rationale
Correct Answer: B
To find what percent 165 is of 150, divide 165 by 150 and then multiply by 100. This calculation yields 110%, indicating that 165 is 110% of 150. Option A (95%) underestimates the value, as it suggests 165 is less than 150. Option C (111%) slightly overestimates the percentage, as it does not accurately reflect the calculation. Option D (115%) also exaggerates the value, implying that 165 exceeds 150 by a larger margin than it actually does. Therefore, 110% is the precise representation of 165 in relation to 150.
To find what percent 165 is of 150, divide 165 by 150 and then multiply by 100. This calculation yields 110%, indicating that 165 is 110% of 150. Option A (95%) underestimates the value, as it suggests 165 is less than 150. Option C (111%) slightly overestimates the percentage, as it does not accurately reflect the calculation. Option D (115%) also exaggerates the value, implying that 165 exceeds 150 by a larger margin than it actually does. Therefore, 110% is the precise representation of 165 in relation to 150.
Frederica used 13.4 gallons of gasoline to drive 448.9 miles. What was the average number of miles she drove per gallon of gasoline?
- A. 3.4 mpg
- B. 33.5 mpg
- C. 60.15 mpg
- D. 435.5 mpg
Correct Answer & Rationale
Correct Answer: B
To find the average miles per gallon (mpg), divide the total miles driven by the gallons used. Here, 448.9 miles divided by 13.4 gallons equals approximately 33.5 mpg. Option A (3.4 mpg) is incorrect as it significantly underestimates the fuel efficiency. Option C (60.15 mpg) overestimates the efficiency, suggesting an unrealistic performance for a typical vehicle. Option D (435.5 mpg) is also incorrect, as it implies an implausibly high efficiency that is not achievable with conventional vehicles. Thus, the calculation confirms that 33.5 mpg accurately represents Frederica's fuel efficiency.
To find the average miles per gallon (mpg), divide the total miles driven by the gallons used. Here, 448.9 miles divided by 13.4 gallons equals approximately 33.5 mpg. Option A (3.4 mpg) is incorrect as it significantly underestimates the fuel efficiency. Option C (60.15 mpg) overestimates the efficiency, suggesting an unrealistic performance for a typical vehicle. Option D (435.5 mpg) is also incorrect, as it implies an implausibly high efficiency that is not achievable with conventional vehicles. Thus, the calculation confirms that 33.5 mpg accurately represents Frederica's fuel efficiency.
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.
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.