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. At a comic book store, Robert purchased three comics for $2.65 each. If he paid with a $20 bill, how much change did he receive?

Correct answer: A

Rationale: Robert spent a total of $7.95 on three comics ($2.65 each). When he paid with a $20 bill, the change he received can be calculated by subtracting the total cost from the payment amount: $20 - $7.95 = $12.05. Therefore, Robert received $12.05 in change. Choice B ($11.05) is incorrect because it doesn't reflect the correct calculation. Choice C ($10.00) is incorrect as it doesn't consider the total cost of the comics. Choice D ($13.50) is incorrect as it overestimates the change Robert received.

3. What is the perimeter of a garden bed with a side length of 8 meters?

Correct answer: B

Rationale: The correct answer is B: 24m. The perimeter of a square is found by adding up all its sides. In this case, since the garden bed has a side length of 8 meters, the perimeter would be 8m + 8m + 8m + 8m = 24m. Choices A, C, and D are incorrect because they do not correctly calculate the perimeter of a square with a side length of 8 meters.

4. Which numeric system was a base 20 system?

Correct answer: A

Rationale: The Mayan numeric system was a base 20 system, known as vigesimal, as it used base 20 numerals. This system was unique and employed a combination of symbols and positional notation to represent numbers. The Babylonian system was a base 60 system, Roman numerals were based on combinations of letters, and Arabic numerals are in base 10, making choices B, C, and D incorrect.

5. If 30% of a given number is 18, what is the full number?

Correct answer: A

Rationale: If 30% of a number is 18, you can find the full number by dividing 18 by 0.30 (the decimal equivalent of 30%). This calculation results in 60. Therefore, the full number is 60. Choice B (30) is the result if 30% of the number itself was calculated, not the full number. Choices C (40) and D (45) are incorrect and do not align with the given information.

Similar Questions

Multiply: 25 × 4 = and express the result in decimal form.
Convert 45 kg to pounds.
How many feet are in 2 miles?
Bai Lin estimates that of her monthly paycheck, she puts 10% in savings and spends 30% on living expenses. If she has $1,545 left after that, how much is her monthly paycheck?
What is the result of subtracting 8.4 from 3.7?

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