a dice is rolled what is the probability of getting an even number

HESI A2

HESI A2 Math Practice

1. If a dice is rolled, what is the probability of getting an even number?

A. 16%
B. 33%
C. 66%
D. 50%

Correct answer: D

Rationale: When rolling a standard six-sided die, there are three even numbers (2, 4, 6) out of a total of six possible outcomes (1, 2, 3, 4, 5, 6). The probability of rolling an even number can be calculated as the number of favorable outcomes (3) divided by the total number of outcomes (6), which equals 3/6 = 50%. Therefore, the correct answer is D. Choice A (16%) is incorrect because it does not represent the probability of rolling an even number. Choice B (33%) is incorrect as it does not reflect the correct probability. Choice C (66%) is incorrect as well since it overestimates the probability.

2. A scientific illustrator uses a scale of 3:1 for drawings of insects. If the length of a cicada in the drawing is 6 centimeters, how long is the actual cicada in real life?

A. 18 centimeters
B. 6.3 centimeters
C. 4.6 centimeters
D. 4.2 centimeters

Correct answer: A

Rationale: The scale of 3:1 means that for every 3 centimeters in the drawing, it represents 1 centimeter in real life. If the length of the cicada in the drawing is 6 centimeters, in real life, it would be 6 x 3 = 18 centimeters long. Therefore, the actual length of the cicada in real life is 18 centimeters. Choice B, 6.3 centimeters, is incorrect because it does not account for the scale factor. Choices C and D, 4.6 centimeters and 4.2 centimeters respectively, are also incorrect as they do not consider the 3:1 scale used in the drawing.

3. Donald earns 8% of the selling price of each house he sells. If he sells a house for $152,000, how much does he earn?

A. $12,160
B. $12,160
C. $19,000
D. $21,600

Correct answer: B

Rationale: To calculate how much Donald earns from selling a house for $152,000 at an 8% commission rate, we multiply the selling price by the commission rate: $152,000 x 0.08 = $12,160. Therefore, he earns $12,160. Choice A, $12,160, is the correct answer as calculated. Choices C and D are incorrect amounts as they do not result from the given information. Choice C, $19,000, is significantly higher than the correct calculation, and choice D, $21,600, is the result of incorrectly adding the commission to the selling price instead of calculating the commission earned.

4. What is the result of multiplying 7.2 by 0.34?

A. 14.12
B. 0.234
C. 7.64
D. 2.448

Correct answer: D

Rationale: To find the result of multiplying 7.2 by 0.34, multiply these two numbers: 7.2 x 0.34 = 2.448. The correct answer is 2.448. Choice A, 14.12, is incorrect as it seems to be the sum of the two numbers. Choice B, 0.234, is incorrect as it is much smaller than the expected result. Choice C, 7.64, is incorrect as it is the result of adding the two numbers rather than multiplying them.

5. What is the opposite of -3?

A. -6
B. 3
C. 0
D. 6

Correct answer: B

Rationale: The opposite of a number is the number that, when added to it, results in zero. In this case, the opposite of -3 is a number that, when added to -3, gives 0. Therefore, the opposite of -3 is 3, as -3 + 3 = 0. Choice A, -6, is incorrect because -3 + (-6) = -9, not zero. Choice C, 0, is the additive inverse of 0, not -3. Choice D, 6, is also incorrect as -3 + 6 = 3, not zero.