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. Jill saved $140 out of the $400 she earned in one month. What percent of her earnings did she save?

A. 30%
B. 35%
C. 40%
D. 25%

Correct answer: B

Rationale: To calculate the percentage of her earnings that Jill saved, divide the amount saved ($140) by the total earnings ($400) and then multiply by 100 to find the percentage. Therefore, (140/400) * 100 = 35%. Jill saved 35% of her earnings. Choice A (30%) is incorrect because it underestimates the percentage saved. Choice C (40%) is incorrect as it overestimates the percentage saved. Choice D (25%) is incorrect for the same reason. The correct calculation is 140/400 = 0.35 * 100 = 35%.

3. The order of operations (PEMDAS) dictates the sequence for evaluating mathematical expressions. If a = 2 and b = -3, what is the value of 3a^2 - 2ab + b^2?

A. -3
B. 0
C. 33
D. 15

Correct answer: C

Rationale: Given expression: 3a^2 - 2ab + b^2. Substitute the values of a and b: 3(2)^2 - 2(2)(-3) + (-3)^2 = 3(4) + 12 + 9 = 12 + 12 + 9 = 24 + 9 = 33. Therefore, the value of the expression is 33, which corresponds to option C. Options A, B, and D are incorrect as they do not accurately evaluate the expression with the given values of a and b.

4. How many centimeters are in 1 foot?

A. 30.48
B. 35
C. 25
D. 40

Correct answer: A

Rationale: The correct answer is A, which is 30.48. To convert inches to feet, since there are 12 inches in a foot, you need to multiply the conversion factor from inches to centimeters (2.54 cm) by the number of inches in a foot (12). This gives 30.48 cm in 1 foot. Choice B, 35, is incorrect as it does not follow the correct conversion. Choices C and D, 25 and 40 respectively, are also incorrect conversions and do not align with the conversion factors provided in the question.