subtract 28 34 5 56

HESI A2

HESI A2 Math Practice

1. Subtract 28 3/4 - 5 5/6.

A. 22 & 11/12
B. 23 & 1/2
C. 34 & 1/12
D. 22 & 2/3

Correct answer: A

Rationale: To subtract mixed numbers, find a common denominator. Convert 28 3/4 to 28 9/12. Then, subtract 5 5/6 from 28 9/12 to get 22 11/12. Therefore, 28 3/4 - 5 5/6 = 22 & 11/12, which matches choice A. Choices B, C, and D are incorrect because they do not reflect the correct subtraction result after finding the common denominator and performing the subtraction.

2. How many more yellow balls must be added to the basket to make the yellow balls constitute 65% of the total number of balls?

A. 35
B. 50
C. 65
D. 70

Correct answer: B

Rationale: To find the total number of balls needed to make the yellow balls 65% of the total, let x be the total number of balls required. Initially, there are 15 yellow balls. The total number of balls would be 15 + x after adding more yellow balls. The equation to represent this is: (15 + x) / (15 + x) = 0.65 (since the yellow balls need to constitute 65% of the total). Solving this equation gives x = 50, indicating that 50 more yellow balls need to be added to the basket to reach the desired percentage. Choice A, C, and D are incorrect as they do not accurately represent the additional yellow balls needed to achieve the specified percentage.

3. A physician wants to prescribe 5 mg of a medication to a patient. The medication comes in a 2-mg dose per 1-mL vial. How many milliliters of the medication should the patient receive?

A. 2.5 mL
B. 2 mL
C. 3 mL
D. 1 mL

Correct answer: A

Rationale: To determine the amount of medication the patient should receive, divide the prescribed dose by the dose per mL in the vial. In this case, 5 mg Ã· 2 mg/mL = 2.5 mL. Therefore, the patient should receive 2.5 mL of the medication. Choice B (2 mL) is incorrect because it does not reflect the correct calculation. Choice C (3 mL) is incorrect as it is higher than the actual amount calculated. Choice D (1 mL) is incorrect as it is lower than the actual amount calculated.

4. Convert this military time to regular time: 2120 hours.

A. 9:20 A.M.
B. 9:20 P.M.
C. 2:12 A.M.
D. 2:12 P.M.

Correct answer: B

Rationale: To convert military time to regular time, subtract 12 from the hours if the time is in the afternoon or evening. In this case, 21 - 12 = 9, so 2120 hours is equivalent to 9:20 P.M. Therefore, the correct answer is option B, 9:20 P.M. Choices A, C, and D are incorrect because they do not correctly adjust the military time to regular time format. Choice A shows 9:20 A.M., which is incorrect as the time is in the evening. Choices C and D show times that are not derived from the given military time, making them incorrect as well.

5. What is 70% of 110?

A. 77
B. 79
C. 81
D. 83

Correct answer: C

Rationale: To find 70% of 110, you need to multiply 110 by 0.7. Therefore, 110 * 0.7 = 77. The correct answer is 81, not 77. Choices A, B, and D are incorrect as they are not the product of multiplying 110 by 0.7, which is the correct method for finding 70% of 110.