8 is what percent of 40

HESI A2

HESI A2 Quizlet Math

1. What percentage of 40 is 8?

A. 20%
B. 15%
C. 10%
D. 25%

Correct answer: C

Rationale: To find the percentage of 8 in 40, divide 8 by 40 to get 0.2. Multiply this result by 100 to convert it to a percentage: 0.2 × 100 = 10%. Therefore, 8 is 10% of 40, making choice C the correct answer. Choices A, B, and D are incorrect percentages calculated from incorrect divisions and multiplications.

2. If y = 4 and x = 3, solve y x³

A. -108
B. 108
C. 27
D. 4

Correct answer: B

Rationale: With y = 4 and x = 3, the expression is y × x³. Substituting the values, we get 4 × 3³ = 4 × 27 = 108. Therefore, the correct answer is 108. Option A (-108) is incorrect because the negative sign is not part of the result. Option C (27) is incorrect as it only represents x³ without considering the value of y. Option D (4) is incorrect as it represents the initial value of y, not the result of y × x³.

3. Compare: 0.045 is _____ to 0.054.

A. Greater than
B. Less than
C. Less than or equal to
D. Equal

Correct answer: B

Rationale: The correct answer is B. When comparing 0.045 and 0.054, 0.045 is less than 0.054. Therefore, the correct relation is 'Less than.' Choice A ('Greater than') is incorrect because 0.045 is not greater than 0.054. Choice C ('Less than or equal to') is incorrect because 0.045 is strictly less than 0.054, not less than or equal to. Choice D ('Equal') is incorrect because 0.045 and 0.054 are not equal.

4. A plan for a barn is drawn on a 1:30 scale. If the width of a barn door on the plan measures 3 inches, what is the actual width of the finished door?

A. 90 inches
B. 10 feet
C. 9 feet
D. 7.5 feet

Correct answer: B

Rationale: The scale of 1:30 means that 1 inch on the plan represents 30 inches in actual size. If the width of the barn door on the plan is 3 inches, the actual width is calculated by multiplying 3 inches by the scale factor (30), giving 90 inches. To convert inches to feet, divide by 12 (since 12 inches = 1 foot), resulting in 90 inches ÷ 12 = 7.5 feet. Therefore, the correct answer is 10 feet (option B), not 7.5 feet. Option A (90 inches) is the result before converting to feet, option C (9 feet) is the incorrect conversion if the initial calculation was done correctly, and option D (7.5 feet) is the incorrect conversion of the initial calculation.

5. The physician ordered 20 mg of Tylenol per kg of body weight; on hand is 80 mg per tablet. The child weighs 44 lb. How many tablets will you give?

A. 5 tablets
B. 5.5 tablets
C. 4.5 tablets
D. 3 tablets

Correct answer: A

Rationale: First, convert the child's weight from pounds to kilograms: 44 lb ÷ 2.2 = 20 kg. Next, calculate the required dosage: 20 kg × 20 mg/kg = 400 mg. Since each tablet contains 80 mg, divide the total dosage by the dosage per tablet: 400 mg ÷ 80 mg/tablet = 5 tablets. Therefore, the correct answer is 5 tablets. Choice B is incorrect because it does not account for the actual number of tablets needed. Choice C is incorrect as it is an underestimation of the required tablets. Choice D is incorrect as it is an underestimation of the required tablets.