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. A medication must be taken twice daily, 12 hours apart. If the first dose is at 8:00 AM, what is the most convenient time for the second dose to avoid disrupting sleep?

A. 4:00 PM
B. 6:00 PM
C. 8:00 PM
D. 10:00 PM

Correct answer: B

Rationale: To take the medication 12 hours apart from the first dose at 8:00 AM, the second dose should be taken at 8:00 PM. However, to avoid disrupting sleep, it is recommended to take the second dose a bit earlier. Taking the second dose at 6:00 PM ensures that the medication is still being taken 12 hours apart while allowing for a buffer before bedtime to avoid any potential disruptions to sleep. Choice A (4:00 PM) is too early, not maintaining the 12-hour interval. Choice C (8:00 PM) aligns with the 12-hour interval but might be too close to bedtime, potentially causing sleep disruptions. Choice D (10:00 PM) is too late and exceeds the 12-hour interval.

3. A stop sign has five equal sides, each measuring 25cm. What is its perimeter?

A. 100cm
B. 125cm
C. 150cm
D. 175cm

Correct answer: C

Rationale: Rationale: - Since a stop sign has five equal sides, each measuring 25cm, the perimeter can be calculated by adding up the lengths of all five sides. - Perimeter = 25cm + 25cm + 25cm + 25cm + 25cm = 125cm - Therefore, the perimeter of the stop sign is 125cm.

4. Subtract 28 3/4 - 5 5/6.

A. 22 & 11/12
B. 23 & 1/2
C. 34 & 1/12
D. 22 & 2/3

Correct answer: A

Rationale: To subtract mixed numbers, find a common denominator. Convert 28 3/4 to 28 9/12. Then, subtract 5 5/6 from 28 9/12 to get 22 11/12. Therefore, 28 3/4 - 5 5/6 = 22 & 11/12, which matches choice A. Choices B, C, and D are incorrect because they do not reflect the correct subtraction result after finding the common denominator and performing the subtraction.

5. How many kilometers are there in 12 miles?

A. 7.5 kilometers
B. 13.2 kilometers
C. 19.2 kilometers
D. 22 kilometers

Correct answer: C

Rationale: To convert miles to kilometers, you can use the conversion factor of 1 mile is equal to 1.609 kilometers. Therefore, to find the number of kilometers in 12 miles, you can multiply 12 miles by 1.609 to get 19.2 kilometers. The correct answer is 19.2 kilometers, making choice C the correct option. Choice A (7.5 kilometers) is incorrect because it represents half the correct conversion. Choice B (13.2 kilometers) is incorrect as it does not apply the correct conversion factor. Choice D (22 kilometers) is incorrect and represents an incorrect conversion calculation.