how many milligrams are in 7 grams

HESI A2

Math HESI A2 Practice Test

1. How many milligrams are in 7 grams?

A. 7000 mg
B. 7 mg
C. 700 mg
D. 70 mg

Correct answer: A

Rationale: To convert grams to milligrams, you need to multiply by 1,000 since there are 1,000 milligrams in a gram. So, 1,000 x 7 grams = 7,000 mg. This means that there are 7,000 milligrams in 7 grams. Choices B, C, and D are incorrect because they do not correctly convert grams to milligrams.

2. Convert 2/5 to a decimal.

A. 0.5
B. 0.25
C. 0.4
D. 0.5

Correct answer: C

Rationale: To convert 2/5 to a decimal, you divide the numerator (2) by the denominator (5): 2 ÷ 5 = 0.4. Therefore, the correct decimal representation of 2/5 is 0.4. Choice A (0.5) is incorrect because it represents 1/2, not 2/5. Choice B (0.25) is incorrect as it represents 1/4, not 2/5. Choice D (0.5) is incorrect as it also represents 1/2, not 2/5.

3. A farmer wants to plant trees around the outside boundaries of his rectangular field with dimensions of 650 meters × 780 meters. Each tree requires 5 meters of free space all around it from the stem. How many trees can he plant?

A. 572
B. 568
C. 286
D. 282

Correct answer: C

Rationale: To determine the number of trees, reduce the field dimensions by 10 meters (5 meters of space on each side). The effective area is 640 meters × 770 meters. Each tree occupies 10 meters × 10 meters. Dividing the effective area by the space for each tree gives: (640 × 770) ÷ (10 × 10) = 286 trees. Choice A, B, and D are incorrect because they do not consider the reduction in field dimensions and the space required for each tree.

4. What is 80% of 55?

A. 40
B. 44
C. 39
D. 45

Correct answer: B

Rationale: To find 80% of a number, you multiply the number by 0.8. Therefore, 80% of 55 is calculated as 0.8 × 55 = 44. Choice A (40), choice C (39), and choice D (45) are incorrect as they do not represent the correct calculation for 80% of 55.