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. 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. What is the freezing point of water in degrees Celsius?

A. 0°C
B. 100°C
C. 50°C
D. 25°C

Correct answer: A

Rationale: The correct answer is 0°C. The freezing point of water is 0°C under standard conditions. Water freezes at 0°C and boils at 100°C. Choices B, C, and D are incorrect because they do not represent the freezing point of water. 100°C is the boiling point of water, 50°C and 25°C are not related to the freezing point of water.

4. How many grams are in 4 kilograms?

A. 4000 grams
B. 3000 grams
C. 4500 grams
D. 3500 grams

Correct answer: A

Rationale: The correct answer is A: 4000 grams. To convert kilograms to grams, you need to multiply the number of kilograms by 1000 since there are 1000 grams in 1 kilogram. Therefore, 4 kilograms is equal to 4 x 1000 = 4000 grams. Choice B (3000 grams), C (4500 grams), and D (3500 grams) are incorrect as they do not correctly convert 4 kilograms into grams.

5. How many liters are in 300 milliliters?

A. 0.03 liters
B. 3 liters
C. 0.3 liters
D. 0.003 liters

Correct answer: C

Rationale: To convert milliliters to liters, you need to divide by 1000 since there are 1000 milliliters in 1 liter. Therefore, 300 milliliters ÷ 1000 = 0.3 liters. Choice A, 0.03 liters, is the result of dividing by 10 instead of 1000. Choice B, 3 liters, is the result of multiplying instead of dividing. Choice D, 0.003 liters, is the result of dividing by 1000 twice, which is incorrect.