a childs toy block is a cube with side lengths of 5cm what is its total surface area

HESI A2

HESI A2 Math Portion

1. A child's toy block is a cube with side lengths of 5cm. What is its total surface area?

A. 25 sq cm
B. 50 sq cm
C. 125 sq cm
D. 150 sq cm

Correct answer: D

Rationale: The surface area of a cube is calculated using the formula: 6 * (side length)^2. Substituting the side length of 5cm into the formula, we get: 6 * (5cm)^2 = 6 * 25cm^2 = 150 sq cm. Therefore, the total surface area of the toy block is 150 sq cm. Choices A (25 sq cm), B (50 sq cm), and C (125 sq cm) are incorrect as they do not correctly calculate the total surface area of the cube.

2. Express 0.025 as a ratio.

A. 1:40
B. 4:1
C. 400:1
D. 26:40:00

Correct answer: A

Rationale: To convert 0.025 to a ratio, we can express it as 25:1000 and simplify it by dividing both terms by 25, resulting in 1:40. Therefore, the correct answer is A. Choice B (4:1) and C (400:1) do not represent the correct ratio for 0.025. Choice D (26:40:00) is incorrect as it does not follow the standard ratio format of two numbers separated by a colon.

3. X/4 = 9/x, solve for x.

A. x = 6
B. x = 3
C. x = 9
D. x = 2

Correct answer: A

Rationale: To solve X/4 = 9/x, cross multiply to get x^2 = 36. Taking the square root of both sides gives x = 6. Choice A is correct because x = 6 satisfies the equation x^2 = 36. Choices B, C, and D are incorrect as they do not satisfy the equation when substituted back into it.

4. What is 70% of 110?

A. 77
B. 79
C. 81
D. 83

Correct answer: C

Rationale: To find 70% of 110, you need to multiply 110 by 0.7. Therefore, 110 * 0.7 = 77. The correct answer is 81, not 77. Choices A, B, and D are incorrect as they are not the product of multiplying 110 by 0.7, which is the correct method for finding 70% of 110.

5. What is the product of 375 and 2.3?

A. 862.5
B. 750
C. 225.75
D. 1125

Correct answer: A

Rationale: To find the product of 375 and 2.3, multiply them: 375 × 2.3 = 862.5. When multiplying by 2.3, it is important to shift the decimal point appropriately after performing the calculation. Choice A, 862.5, is the correct answer. Choice B, 750, is incorrect because it is the result of multiplying 375 by 2. Choice C, 225.75, is incorrect as it appears to be the result of multiplying the numbers in the wrong order. Choice D, 1125, is incorrect as it seems to be the result of multiplying 375 by 3 instead of 2.3.