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

Nursing Elites

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?

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. A medication order is for 250 micrograms of a drug to be administered subcutaneously. The available syringe measures in milliliters. How many milliliters should the healthcare professional draw up?

Correct answer: D

Rationale: 1 milliliter (mL) is equal to 1000 micrograms (mcg). Therefore, to find out how many milliliters are needed for 250 micrograms: 250 mcg ÷ 1000 = 0.25 mL. So, the healthcare professional should draw up 0.25 milliliters of the drug to administer 250 micrograms subcutaneously. Choice A, 0.00025 milliliters, is incorrect as it is too small a volume for the required dosage. Choice B, 0.0025 milliliters, is also too small. Choice C, 0.025 milliliters, is 100 times greater than the correct answer of 0.25 milliliters. Therefore, the correct answer is 0.25 milliliters.

3. Express 4/5 as a percent.

Correct answer: D

Rationale: To convert a fraction to a percentage, you multiply the fraction by 100. To express 4/5 as a percent, you perform the calculation 4/5 * 100 = 80%. Therefore, the correct answer is D, 80%. Choices A, B, and C are incorrect as they do not represent the correct conversion of 4/5 to a percentage.

4. What is the average of the numbers 14, 73, and 7?

Correct answer: D

Rationale: The correct answer is D. Adding 14 + 73 + 7 gives a total of 94. To find the average, we divide the sum by the number of values (3), which equals 31.33. Rounding this average to two decimal places gives us 31.33, which corresponds to option D. Choices A, B, and C are incorrect as they do not correctly calculate the average of the given numbers. Choice A is close to the sum of the numbers, not the average. Choices B and C are also not correct averages calculated from the provided numbers.

5. A family uses 12 gallons of water every day. How many gallons do they use in a non-leap year?

Correct answer: B

Rationale: To determine the total gallons the family uses in a non-leap year, you have to multiply the daily consumption by the number of days in a non-leap year. So, 12 gallons/day x 365 days = 4,380 gallons used per year. Therefore, the correct answer is B. Choice A is incorrect as it provides an inaccurate total by not considering the total days in a year. Choice C is incorrect as it offers a lower value due to not multiplying the daily usage by the total days in a year. Choice D is incorrect as it doesn't accurately calculate the total gallons used in a non-leap year.

Similar Questions

In a bowling team consisting of 34 members, with 18 being male, if 4 females leave the team, what percent of the remaining members are male?
Subtract and simplify: 8¼ − 1½.
A doctor prescribes 150 milligrams of medication to be taken orally every 12 hours. How many grams should the patient take per dose?
How many gallons are in 3 fluid ounces?
What is the probability of rolling a 2 on a six-sided die?

Access More Features

HESI A2 Basic
$89/ 30 days

  • 3,000 Questions with answers
  • 30 days access

HESI A2 Premium
$129.99/ 90 days

  • Actual HESI A2 Questions
  • 3,000 questions with answers
  • 90 days access

Other Courses