if 30 of a given number is 18 what is the full number

HESI A2

HESI A2 Practice Test Math

1. If 30% of a given number is 18, what is the full number?

A. 60
B. 30
C. 40
D. 45

Correct answer: A

Rationale: If 30% of a number is 18, you can find the full number by dividing 18 by 0.30 (the decimal equivalent of 30%). This calculation results in 60. Therefore, the full number is 60. Choice B (30) is the result if 30% of the number itself was calculated, not the full number. Choices C (40) and D (45) are incorrect and do not align with the given information.

2. What time is 6:30 A.M. in military time?

A. 0630
B. 6030
C. 1503
D. 1530

Correct answer: A

Rationale: Military time uses a 24-hour clock format where the hours range from 00 to 23. In this format, 6:30 A.M. is expressed as 0630. Choice B (6030) and Choice C (1503) are incorrect as they do not follow the 24-hour clock format. Choice D (1530) represents 3:30 P.M., not 6:30 A.M.

3. A patient is prescribed 500 mg of medication, but the available tablets are 250 mg each. How many tablets should be given?

A. 3 tablets
B. 2 tablets
C. 4 tablets
D. 5 tablets

Correct answer: B

Rationale: To find out how many tablets of 250 mg are needed to reach a total of 500 mg, you divide the total prescribed dosage by the dosage per tablet. In this case, 500 mg / 250 mg per tablet = 2 tablets. Therefore, the correct answer is 2 tablets. Choice A (3 tablets) is incorrect because it would exceed the prescribed dosage. Choices C (4 tablets) and D (5 tablets) are incorrect as they would also provide more medication than needed.

4. What is the result of dividing 3.44 by 0.6 rounded off to the nearest whole number?

A. 0
B. 6
C. 11
D. 2

Correct answer: B

Rationale: To find the result of dividing 3.44 by 0.6, you perform the division operation: 3.44 ÷ 0.6 = 5.73. When rounded off to the nearest whole number, 5.73 becomes 6. Therefore, the correct answer is 6. Choice A is incorrect as the result is not 0. Choice C is incorrect as it is not the closest whole number to 5.73. Choice D is incorrect as it does not reflect the accurate division result.

5. There are 6,657 marbles in a jar. Approximately 34% are white, and the rest are black. How many black marbles are there?

A. 4,394
B. 4,000
C. 3,000
D. 5,000

Correct answer: A

Rationale: To find the number of black marbles, we need to calculate the percentage that represents the black marbles, which is 100% - 34% = 66%. Then, we find 66% of 6,657 to determine the number of black marbles. 66% of 6,657 is approximately 4,394, so there are 4,394 black marbles in the jar. Choice A is correct. Choices B, C, and D are incorrect as they do not reflect the correct calculation for the number of black marbles in the jar.