what is the sum of 37 47 and 27

HESI A2

HESI A2 Math Practice

1. What is the sum of 3/7, 4/7, and 2/7?

A. 7/7
B. 9/7
C. 6/7
D. 7/7

Correct answer: B

Rationale: To find the sum of fractions with the same denominator, add the numerators. Here, 3/7 + 4/7 + 2/7 = (3 + 4 + 2)/7 = 9/7. Therefore, the correct answer is 9/7. Choice A (7/7) is incorrect as the sum is not 7/7. Choice C (6/7) is incorrect as the sum is not 6/7. Choice D (7/7) is incorrect as the sum is not 7/7.

2. A lab needs 200ml of a 5% salt solution. They only have a 10% solution. How much 10% solution and water should be mixed?

A. 100ml 10% solution, 100ml water
B. 150ml 10% solution, 50ml water
C. 160ml 10% solution, 40ml water
D. 200ml 10% solution, 0ml water

Correct answer: B

Rationale: Rationale: 1. Let x be the volume of the 10% solution needed and y be the volume of water needed. 2. The total volume of the final solution is 200ml, so x + y = 200. 3. The concentration of the final solution is 5%, so the amount of salt in the final solution is 0.05 * 200 = 10g. 4. The amount of salt in the 10% solution is 0.1x, and the amount of salt in the water is 0, so the total amount of salt in the final solution is 0.1x. 5. Since the total amount of salt in the final solution is 10g, we have 0.1x = 10. 6. Solving for x, we get x = 100ml. 7. Substituting x =

3. Joe makes $20 an hour and Tim makes $30 an hour. How many more hours than Tim must Joe work to earn the same amount that Tim makes in 4 hours?

A. 1 hour
B. 2 hours
C. 3 hours
D. 4 hours

Correct answer: B

Rationale: To earn the same amount that Tim makes in 4 hours, Tim earns $30 per hour, totaling $120 in 4 hours. Joe earns $20 per hour, so to match Tim's earnings in 4 hours, Joe must work 2 hours more than Tim. Therefore, Joe needs to work 2 hours more than Tim to earn the same amount that Tim makes in 4 hours. Choices A, C, and D are incorrect as they do not accurately reflect the additional hours Joe needs to work compared to Tim to earn the same amount in 4 hours.

4. What is the result of the expression 47/57 + 65/75?

A. 1 23/35
B. 2 1/3
C. 1 2/3
D. 1 5/6

Correct answer: A

Rationale: To add fractions, you need a common denominator. In this case, the common denominator is 57 * 75 = 4275. So, (47*75 + 65*57) / 4275 = (3525 + 3705) / 4275 = 7230 / 4275. Simplifying this fraction gives 1 23/35. Choice B: 2 1/3 is incorrect as the correct result is not a mixed number. Choice C: 1 2/3 is incorrect as it does not match the simplified result of the expression. Choice D: 1 5/6 is incorrect as it is a different value from the correct result obtained by adding the fractions.

5. What is the probability of rolling a 3 on a six-sided die?

A. 1/6
B. 1/4
C. 1/3
D. 1/2

Correct answer: A

Rationale: The probability of rolling a specific number on a six-sided die is calculated by dividing the favorable outcomes (rolling a 3) by the total possible outcomes. In this case, there is 1 favorable outcome (rolling a 3) out of 6 total possible outcomes (numbers 1 to 6 on the die). Therefore, the probability of rolling a 3 is 1/6. Choice B (1/4), C (1/3), and D (1/2) are incorrect because they do not represent the correct calculation of the probability for rolling a 3 on a six-sided die.