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. If a man reads 2 chapters a day and there are 6 pages per chapter in a 798-page book, how long will it take him to finish the book?

A. 133 days
B. 399 days
C. 75 days
D. 66.5 days

Correct answer: D

Rationale: To find the total number of chapters, divide the total number of pages by the number of pages per chapter: 798 ÷ 6 = 133 chapters. If he reads 2 chapters a day, it will take him 133 ÷ 2 = 66.5 days to finish the book. Therefore, the correct answer is 66.5 days. Choice A is incorrect because it miscalculates the number of days required. Choices B and C are incorrect as they do not consider the correct calculation based on the given information.

3. A train travels at 80 mph for 3 hours. How far did it travel?

A. 240 miles
B. 160 miles
C. 280 miles
D. 320 miles

Correct answer: A

Rationale: To calculate the distance traveled, you multiply the speed of the train (80 mph) by the time it traveled (3 hours): 80 mph × 3 hours = 240 miles. Therefore, the correct answer is 240 miles. Choice B (160 miles) is incorrect because it results from multiplying the speed by the incorrect time. Choices C (280 miles) and D (320 miles) are incorrect as they represent calculations that do not match the given speed and time.

4. Evaluate the following expression: -x + y + xy, when x = 4 and y = 2.

A. 2
B. 6
C. 12
D. 8

Correct answer: B

Rationale: To evaluate the expression, substitute x = 4 and y = 2 into the expression: -4 + 2 + 4*2. Calculate each term: -4 + 2 = -2, then 4*2 = 8. Adding these results gives -2 + 8 = 6. Therefore, the correct answer is 6. Choice A (2) is incorrect as it does not consider all terms in the expression. Choice C (12) is incorrect as it miscalculates the result by failing to account for the negative sign. Choice D (8) is incorrect as it doesn't consider the negative value of the first term in the expression.

5. What is the temperature in Celsius when it is 98.6 degrees Fahrenheit?

A. 35 Celsius
B. 37 Celsius
C. 38 Celsius
D. 36.5 Celsius

Correct answer: B

Rationale: To convert 98.6 degrees Fahrenheit to Celsius, you can use the formula (98.6 - 32) × 5/9. By solving this equation, the temperature is calculated to be 37°C. Therefore, the correct answer is B, 37 Celsius. Choice A, 35 Celsius, is incorrect because it is not the outcome of the conversion formula. Choice C, 38 Celsius, is incorrect as well, as it does not match the correct conversion result. Choice D, 36.5 Celsius, is also incorrect as it does not correspond to the accurate conversion from 98.6 degrees Fahrenheit.