evaluate the following expression x y xy if x 4 and y 2

HESI A2

HESI A2 Math Practice Exam

1. 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.

2. The recipe called for 3 1/2 pints of sour cream. How many cups of sour cream would that be equivalent to?

A. 5 cups
B. 7 cups
C. 6 cups
D. 4 cups

Correct answer: B

Rationale: To convert 3 1/2 pints of sour cream to cups, knowing that 1 pint equals 2 cups, we multiply 3.5 by 2, resulting in 7 cups. Therefore, the equivalent amount of sour cream in cups is 7 cups. Choice A is incorrect as it does not consider the correct conversion factor. Choice C is incorrect as it does not account for the accurate conversion from pints to cups. Choice D is incorrect as it underestimates the conversion by not multiplying the pints by the correct factor.

3. Karen goes to the grocery store with $40. She buys a carton of milk for $1.85, a loaf of bread for $3.20, and a bunch of bananas for $3.05. How much money does she have left?

A. $30.95
B. $31.90
C. $32.10
D. $34.95

Correct answer: B

Rationale: To determine how much money Karen has left, we first calculate the total cost of the items she bought: $1.85 + $3.20 + $3.05 = $8.10. Subtracting this total cost from the initial amount she had, $40 - $8.10 = $31.90 left. Choice A, $30.95, is incorrect as it does not reflect the correct amount left after subtracting the total cost. Choice C, $32.10, is incorrect as it is the total cost of the items she bought, not the amount left. Choice D, $34.95, is incorrect as it does not consider the expenses incurred and subtracted from the initial amount.

4. Convert 5 3/4 to a decimal. Round to the nearest tenth.

A. 5.6
B. 5.7
C. 5.8
D. 6

Correct answer: C

Rationale: To convert 5 3/4 to a decimal, we add the whole number part to the fractional part: 5 + 3/4 = 5.75. Rounding 5.75 to the nearest tenth gives us 5.8. Therefore, the correct answer is C. Choice A (5.6) is incorrect because it does not accurately represent 5 3/4. Choice B (5.7) is incorrect as well because it does not reflect the correct conversion. Choice D (6) is incorrect as it does not account for the fractional part of 5 3/4.

5. How many pounds are in 48 ounces?

A. 3 lbs
B. 6 lbs
C. 4 lbs
D. 8 lbs

Correct answer: A

Rationale: To convert ounces to pounds, you need to know that there are 16 ounces in a pound. Therefore, to find out how many pounds are in 48 ounces, you divide 48 by 16: 48 Ã· 16 = 3 pounds. This means that 48 ounces is equivalent to 3 pounds. Choice B, 6 lbs, is incorrect as it doesn't correctly convert 48 ounces to pounds. Choice C, 4 lbs, is incorrect as it doesn't take into account the conversion factor of 16 ounces per pound. Choice D, 8 lbs, is also incorrect as it doesn't reflect the accurate conversion of ounces to pounds.