if a dozen roses cost 36 how much will four roses cost

HESI A2

HESI A2 Math Practice Exam

1. If a dozen roses cost $36, how much will four roses cost?

A. $9
B. $12
C. $10
D. $15

Correct answer: B

Rationale: To find the cost of each rose, divide the total cost by the number of roses in a dozen: $36 ÷ 12 = $3 per rose. Therefore, 4 roses will cost 4 × $3 = $12. Choice A ($9) is incorrect because it miscalculates the cost per rose. Choice C ($10) is incorrect as it doesn't consider the correct division of the total cost. Choice D ($15) is incorrect as it overestimates the cost of four roses.

2. Solve for x: 3x + 9 = 0.

A. x = -3
B. x = -3
C. x = 1
D. x = 0

Correct answer: B

Rationale: To solve the equation 3x + 9 = 0, first, isolate the variable x. Subtract 9 from both sides to get 3x = -9. Then, divide by 3 to solve for x, giving x = -3. Therefore, the correct answer is B. Choice A, x = -3, is the correct solution. Choices C and D are incorrect as they do not satisfy the equation when substituted back into it.

3. Edie has 132 tulip bulbs. She wants to plant all of the tulip bulbs in 12 rows. How many bulbs should she plant in each row?

A. 11 bulbs
B. 10 bulbs
C. 12 bulbs
D. 15 bulbs

Correct answer: A

Rationale: To plant 132 bulbs in 12 rows, Edie should plant 11 bulbs in each row. This is calculated by dividing the total number of bulbs by the number of rows: 132 bulbs ÷ 12 rows = 11 bulbs per row. Choice B, 10 bulbs, is incorrect because dividing 132 bulbs by 12 rows does not equal 10. Choice C, 12 bulbs, is incorrect because if Edie plants 12 bulbs in each row, the total number of bulbs planted would exceed 132. Choice D, 15 bulbs, is incorrect as dividing 132 bulbs by 12 rows does not result in 15 bulbs per row.

4. A patient's height is 1.65 meters and their weight is 75kg. Calculate their BMI and interpret the result.

A. 23.1 (Normal)
B. 25.3 (Overweight)
C. 27.7 (Overweight)
D. 32.8 (Obese)

Correct answer: C

Rationale: To calculate BMI, divide weight (75kg) by height squared (1.65m^2) to get BMI (27.7). A BMI of 27.7 falls within the 'overweight' category (25-29.9 BMI). Choice A is incorrect as a BMI of 23.1 would be in the 'normal' range (18.5-24.9 BMI). Choice B is incorrect as 25.3 falls within the 'overweight' category. Choice D is incorrect as 32.8 is in the 'obese' category (>30 BMI). Therefore, the correct answer is C.

5. Express the ratio of 6:7 as a percentage.

A. 67%
B. 76%
C. 86%
D. 93%

Correct answer: A

Rationale: To express the ratio 6:7 as a percentage, we first need to find the total parts in the ratio, which is 6 + 7 = 13. To convert this ratio to a percentage, divide the part you want to find the percentage for by the total parts, then multiply by 100. In this case, to find the percentage for 6 in the ratio 6:7, the calculation would be (6/13) * 100 = 46.15%. Therefore, the correct answer is A, 67%. Choices B, C, and D are incorrect percentages as they do not result from the correct calculation for the given ratio.