if x 2 and m 3 evaluate xm 2m

HESI A2

HESI A2 Practice Test Math

1. If x = -2 and m = -3, evaluate: xm - 2m

A. 12
B. 6
C. 8
D. 10

Correct answer: A

Rationale: Substitute x = -2 and m = -3 into the expression: (-2) * (-3) - 2 * (-3) = 6 + 6 = 12. Therefore, the correct answer is 12. The mistake in the other choices lies in the calculation. Choice B, 6, is the result of adding the two terms instead of subtracting the second term from the first. Choice C, 8, and Choice D, 10, are also incorrect as they do not follow the correct calculation process.

2. A patient's oxygen flow rate is set at 4 liters per minute. How many cubic centimeters of oxygen are delivered per minute?

A. 400 cubic centimeters
B. 4,000 cubic centimeters
C. 40,000 cubic centimeters
D. 400,000 cubic centimeters

Correct answer: B

Rationale: 1 liter is equal to 1,000 cubic centimeters. Therefore, when the oxygen flow rate is 4 liters per minute, the calculation is 4 x 1,000 = 4,000 cubic centimeters. Hence, at a flow rate of 4 liters per minute, 4,000 cubic centimeters of oxygen are delivered per minute. Choice A, 400 cubic centimeters, is incorrect because it miscalculates the conversion from liters to cubic centimeters. Choices C and D, 40,000 cubic centimeters and 400,000 cubic centimeters, respectively, are significantly higher than the correct answer due to incorrect conversions or additional errors in calculation.

3. 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.

4. Which of these dates is represented by the Roman numeral MMXV?

A. 2001
B. 2015
C. 2051
D. 2105

Correct answer: B

Rationale: The Roman numeral MMXV represents the year 2015. In Roman numerals, M represents 1000, X represents 10, and V represents 5. Therefore, by converting the Roman numeral MMXV into its numerical equivalent (1000 + 10 + 5), it corresponds to the year 2015. Choice A (2001) is incorrect as it would be represented as MM + I, choice C (2051) would be represented as MM + LI, and choice D (2105) would be represented as MMCV in Roman numerals, making them all inaccurate representations of MMXV.

5. Multiply: 2 × 5 =

A. 0.013
B. 0.13
C. 1.3
D. 10

Correct answer: D

Rationale: When you multiply 2 by 5, the result is 10, not 13. Therefore, the correct answer is 10, which is option D. Choices A, B, and C are incorrect because they do not represent the correct product of multiplying 2 by 5.