convert 15 to a decimal

HESI A2

Math HESI A2 Practice Test

1. Convert 1/5 to a decimal.

A. 0.5
B. 0.2
C. 1.5
D. 0.15

Correct answer: B

Rationale: To convert a fraction to a decimal, divide the numerator by the denominator. In this case, 1 ÷ 5 = 0.2. Therefore, the correct answer is B. Choice A (0.5) is incorrect because the decimal form of 1/5 is not 0.5. Choice C (1.5) is incorrect as it is the sum of 1 and 0.5, not the decimal form of 1/5. Choice D (0.15) is incorrect as it is the decimal form of 15/100, not 1/5.

2. The physician ordered 3,000 units of heparin; 5,000 U/mL is on hand. How many milliliters will you give?

A. 0.5 ml
B. 0.6 ml
C. 0.75 ml
D. 0.8 ml

Correct answer: B

Rationale: To calculate the volume of heparin needed, use the formula: Volume of Heparin = (Ordered Units / Concentration of Heparin). Substituting the values, Volume = (3,000 units / 5,000 U/mL) = 0.6 ml. Therefore, the correct answer is 0.6 ml. Choice A (0.5 ml) is incorrect as it results from an incorrect calculation. Choices C (0.75 ml) and D (0.8 ml) are also incorrect calculations based on the wrong formula application or mathematical errors.

3. How many inches are in 2 yards?

A. 36 inches
B. 48 inches
C. 60 inches
D. 72 inches

Correct answer: D

Rationale: To convert yards to inches, remember that there are 36 inches in a yard. Therefore, when you have 2 yards, multiplying 36 inches by 2 results in 72 inches. Choice A, 36 inches, is the number of inches in 1 yard, not 2 yards. Choice B, 48 inches, and Choice C, 60 inches, are incorrect calculations based on the conversion factor of 36 inches per yard.

4. A honeycomb cell has six equal sides, each measuring 8mm. What is its perimeter?

A. 32mm
B. 40mm
C. 48mm
D. 56mm

Correct answer: C

Rationale: To find the perimeter of a shape with equal sides, you multiply the length of one side by the number of sides. In this case, the honeycomb cell has 6 sides, each measuring 8mm. Therefore, the perimeter is calculated as perimeter = number of sides * side length = 6 * 8mm = 48mm. Choices A, B, and D are incorrect because they do not correctly calculate the total length around the honeycomb cell with six sides.

5. You need to repaint a cylindrical water tank with a diameter of 2 meters and a height of 3 meters. Assuming one can of paint covers 10 sq m, how many cans do you need to cover only the exterior surface?

A. 6 cans
B. 9 cans
C. 12 cans
D. 15 cans

Correct answer: C

Rationale: To find the surface area of the cylinder, calculate the lateral surface area using the formula 2πrh, where r is the radius (half of the diameter) and h is the height. Substituting the values, we get 2 * π * 1 * 3 = 6π square meters. Since each can covers 10 sq m, divide the total surface area by the coverage area per can: 6π / 10 ≈ 1.9 cans. Since you can't buy a fraction of a can, you would need to round up, so you would need 2 cans to cover the entire exterior surface. Therefore, you would need 2 * 6 = 12 cans in total. Choices A, B, and D are incorrect as they do not consider the correct surface area calculation or the rounding up to the nearest whole number of cans required.