a dice is rolled what is the probability of getting a 5

HESI A2

Math HESI A2 Practice Test

1. A die is rolled. What is the probability of getting a 5?

A. 50%
B. 20%
C. 16.60%
D. 83.30%

Correct answer: C

Rationale: The correct answer is C (16.60%). When rolling a standard 6-sided die, the probability of getting a 5 is 1/6 or approximately 16.6%. Choice A (50%) is incorrect as it represents the probability of getting a specific number on a coin flip, not a die roll. Choice B (20%) is incorrect as it does not reflect the probability of rolling a 5 on a standard die. Choice D (83.30%) is incorrect as it is the complement of the probability of rolling a 5, which is not asked in the question.

2. What is the probability of rolling a 2 on a six-sided die?

A. 1/6
B. 1/4
C. 1/3
D. 1/2

Correct answer: A

Rationale: The correct answer is A: 1/6. A six-sided die has one face with a '2' out of six possible outcomes (numbers 1 to 6). Therefore, the probability of rolling a 2 is 1/6. Choices B, C, and D are incorrect because they do not reflect the specific probability of rolling a 2 on a six-sided die.

3. What is 70% of 200?

A. 100
B. 100
C. 200
D. 140

Correct answer: D

Rationale: To find 70% of a number, you multiply the number by 0.70. Therefore, 70% of 200 is calculated as 0.7 × 200 = 140. Choices A, B, and C are incorrect as they do not represent the correct calculation for finding 70% of 200.

4. A medication order is for 250 micrograms of a drug to be administered subcutaneously. The available syringe measures in milliliters. How many milliliters should the healthcare professional draw up?

A. 0.00025 milliliters
B. 0.0025 milliliters
C. 0.025 milliliters
D. 0.25 milliliters

Correct answer: D

Rationale: 1 milliliter (mL) is equal to 1000 micrograms (mcg). Therefore, to find out how many milliliters are needed for 250 micrograms: 250 mcg ÷ 1000 = 0.25 mL. So, the healthcare professional should draw up 0.25 milliliters of the drug to administer 250 micrograms subcutaneously. Choice A, 0.00025 milliliters, is incorrect as it is too small a volume for the required dosage. Choice B, 0.0025 milliliters, is also too small. Choice C, 0.025 milliliters, is 100 times greater than the correct answer of 0.25 milliliters. Therefore, the correct answer is 0.25 milliliters.

5. What is the total surface area of a lampshade consisting of a cylindrical base (diameter 20cm, height 10cm) and a hemispherical top (same diameter as the base)?

A. 785 sq cm
B. 1130 sq cm
C. 1570 sq cm
D. 2055 sq cm

Correct answer: D

Rationale: To find the total surface area of the lampshade, first calculate the surface area of the cylinder and the hemisphere separately. 1. Surface area of the cylinder = 2πr² + 2πrh = 2π(10)² + 2π(10)(20) = 400π + 400π = 800π cm². 2. Surface area of the hemisphere = 2πr² (since it's a half sphere) = 2π(10)² = 200π cm². Adding both areas gives the total surface area: 800π + 200π = 1000π cm². Now, calculate the numerical value: 1000π ≈ 3141.59 cm², which is approximately equal to 2055 cm². Therefore, the correct answer is 2055 sq cm. Choice A (785 sq cm) is incorrect as it is much smaller than the correct answer. Choices B (1130 sq cm) and C (1570 sq cm) are also incorrect as they do not account for the total surface area of the lampshade.