a lab needs 200ml of a 5 salt solution they only have a 10 solution how much 10 solution and water should be mixed

HESI A2

HESI A2 Math Portion

1. 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 =

2. If Mr. Parker owns 150 shares of stock in Stark Industries and receives $180.00 per year in dividends, how much does Mr. Rogers receive for an annual dividend if he owns 400 shares?

A. $480
B. $500
C. $450
D. $72,000

Correct answer: A

Rationale: To find out how much Mr. Rogers receives for an annual dividend with 400 shares, we can set up a proportion: 400 shares is to X dollars as 150 shares is to $180. This gives us 400 * $180 / 150 = $480 in annual dividends. Therefore, the correct answer is A. Choice B, $500, is incorrect because it does not consider the proportionality of shares to dividend amount. Choice C, $450, is incorrect as it does not reflect the correct calculation based on the given information. Choice D, $72,000, is significantly higher and incorrect as it does not align with the proportionality of shares and dividends.

3. Multiply: 6 × 0.06 =

A. 0.0036
B. 0.036
C. 0.36
D. 3.6

Correct answer: C

Rationale: When multiplying 6 by 0.06, you can treat 0.06 as 6 hundredths. So, 6 × 0.06 is equivalent to 6 × 6 hundredths, which equals 0.36. The correct answer is 0.36. Choice A (0.0036) is incorrect because it represents 6 multiplied by 0.0006, not 0.06. Choice B (0.036) is incorrect as it represents 6 multiplied by 0.06 without considering the position of the decimal point. Choice D (3.6) is incorrect as it represents 6 multiplied by 6, not by 0.06.

4. How many grams are in 5 kilograms?

A. 50,000 grams
B. 500 grams
C. 5,000 grams
D. 50,000 grams

Correct answer: C

Rationale: The correct answer is C: 5,000 grams. There are 1,000 grams in a kilogram. Therefore, to convert kilograms to grams, you need to multiply the number of kilograms by 1,000. In this case, 5 kilograms is equal to 5 × 1,000 = 5,000 grams. Choices A and D are incorrect as they incorrectly multiply by 10,000 instead of 1,000. Choice B is incorrect as it divides instead of multiplies, leading to an incorrect conversion.

5. What is 35% of 70?

A. 17.5
B. 24.5
C. 35
D. 50

Correct answer: B

Rationale: To find 35% of a number, you multiply the number by 0.35. In this case, 35% of 70 is calculated as 70 x 0.35 = 24.5. Choice A (17.5) is incorrect because it represents 25% of 70. Choice C (35) is incorrect as it is the percentage itself, not the result of the calculation. Choice D (50) is incorrect as it does not represent the result of finding 35% of 70.