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 lab test result shows a blood glucose level of 5.5 millimoles per liter (mmol/L). What is the equivalent level in milligrams per deciliter (mg/dL)?

A. 55 mg/dL
B. 5.5 mg/dL
C. 0.55 mg/dL
D. 550 mg/dL

Correct answer: A

Rationale: To convert the blood glucose level from millimoles per liter (mmol/L) to milligrams per deciliter (mg/dL), we need to perform a double conversion. 1 millimole is equivalent to 180.15 milligrams, and 1 liter is equal to 10 deciliters. First, multiply the glucose level (5.5 mmol/L) by the conversion factor for millimoles to milligrams (180.15 mg/mmol), then divide by the conversion factor for liters to deciliters (10 dL/L): 5.5 mmol/L * 180.15 mg/mmol / 10 dL/L ≈ 55 mg/dL. Therefore, the equivalent blood glucose level in mg/dL is 55. Choice A is correct. Choice B is incorrect as it does not account for the conversion factors properly. Choices C and D are significantly off as they do not follow the correct conversion calculations.

3. How many liters are in 120 milliliters?

A. 1.2 liters
B. 12 liters
C. 1,200 liters
D. 0.12 liters

Correct answer: D

Rationale: To convert milliliters to liters, divide the milliliters by 1000 since there are 1000 milliliters in a liter. In this case, 120 milliliters divided by 1000 equals 0.12 liters. Therefore, the correct answer is 0.12 liters. Choice A (1.2 liters) is incorrect as it incorrectly moved the decimal point. Choice B (12 liters) is incorrect as it incorrectly multiplied by 10 instead of dividing by 1000. Choice C (1,200 liters) is incorrect as it added an extra zero, resulting in a much larger value.

4. Which numeric system was a base 20 system?

A. Mayan
B. Babylonian
C. Roman
D. Arabic

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. Solve for y if y = 3: 4y + 21 / y.

A. 7.7
B. 19
C. 23/3
D. 11

Correct answer: B

Rationale: To solve for y, substitute y = 3 into the equation: 4(3) + 21 / 3 = 12 + 7 = 19. Therefore, the correct answer is 19. Choice A (7.7) is incorrect as it does not result from the substitution. Choice C (23/3) is incorrect as it does not match the calculated value. Choice D (11) is incorrect, as it is not the result of the provided equation.