two thirds of the students in mr garcias class are boys if there are 27 students in the class how many of them are girls

HESI A2

Practice HESI A2 Math Test

1. In Mr. Garcia's class, two-thirds of the students are boys. If there are 27 students in the class, how many of them are girls?

A. 1
B. 9
C. 12
D. 20

Correct answer: B

Rationale: If two-thirds of the students are boys, then one-third of the students must be girls. One-third of 27 is 9, so there are 9 girls in Mr. Garcia's class. Therefore, the correct answer is 9. Choice A is incorrect because it is too low; only one-third of the students are girls. Choices C and D are incorrect as they do not reflect the correct calculation based on the given information in the question.

2. What is the result of adding 6 3/4 + 8 1/6?

A. 14 11/12
B. 12 3/4
C. 12 3/24
D. 14 2/5

Correct answer: A

Rationale: To add mixed numbers, convert them to improper fractions: 6 3/4 = 27/4 and 8 1/6 = 49/6. Then, add the fractions to get 27/4 + 49/6 = 162/24 + 98/24 = 260/24 = 21 20/24 = 21 10/12 = 21 5/6 = 14 11/12. Therefore, the correct answer is 14 11/12. Choice B (12 3/4) is incorrect as it does not match the correct calculation. Choice C (12 3/24) is incorrect due to the erroneous denominator in the final fraction. Choice D (14 2/5) is incorrect as it does not correspond to the correct sum of the fractions.

3. How many meters are in 3 kilometers?

A. 3000 meters
B. 2000 meters
C. 3500 meters
D. 2500 meters

Correct answer: A

Rationale: The correct answer is A: 3000 meters. To convert kilometers to meters, you need to know that there are 1000 meters in 1 kilometer. Therefore, to find the number of meters in 3 kilometers, you multiply 3 by 1000, resulting in 3000 meters. Choice B, 2000 meters, is incorrect as it doesn't account for the correct conversion factor. Choice C, 3500 meters, and Choice D, 2500 meters, are also incorrect as they provide inaccurate conversions.

4. Subtract: 15.7 - 9.8 =

A. 6.1
B. 8.96
C. 5.9
D. 4.30

Correct answer: C

Rationale: To find the difference between 15.7 and 9.8, you need to subtract 9.8 from 15.7. This operation results in 5.9. Therefore, the correct answer is 5.9. Choice A, 6.1, is incorrect as it represents the result of subtracting 9.8 from 15.9, not 15.7. Choice B, 8.96, is also incorrect as it is not the correct result of the subtraction provided. Choice D, 4.30, is incorrect as well, as it is not the result of subtracting 9.8 from 15.7.

5. Express the ratio of 13:60 as a percentage.

A. 19.50%
B. 21.67%
C. 25.50%
D. 31%

Correct answer: B

Rationale: To express the ratio 13:60 as a percentage, calculate the decimal form of the ratio by dividing 13 by 60: 13/60 ≈ 0.2167. Next, convert this decimal to a percentage by multiplying by 100: 0.2167 x 100 = 21.67%. Choice A, 19.50%, is incorrect as it does not accurately represent the ratio. Choice C, 25.50%, and Choice D, 31%, are also incorrect calculations of the percentage equivalent of the ratio 13:60.