What is the value of the sum of 3/4 and 5/8?

Correct Answer: D

Rationale: To find the sum of fractions, they need to have a common denominator. In this case, the common denominator is 8. So, 3/4 = 6/8. Adding 6/8 and 5/8 gives 11/8, which simplifies to 1 3/8. Therefore, the correct answer is 1 3/8, which corresponds to choice A. Choices B, C, and D are incorrect as they do not represent the correct sum of 3/4 and 5/8.

Correct Answer: A

Rationale: To find the number that 20 is equal to 40% of, you can set up the equation: 20 = 0.4 * x, where x is the unknown number. To solve for x, divide both sides of the equation by 0.4. This gives x = 20 / 0.4 = 50. Therefore, 20 is 40% of 50. Choice B, 8, is incorrect because 20 is not equal to 40% of 8. Choice C, 200, is incorrect because 20 is not equal to 40% of 200. Choice D, 5000, is incorrect because 20 is not equal to 40% of 5000. The correct answer is 50.

Correct Answer: A

Rationale: When rounding a number to the nearest thousandth, you look at the digit in the ten-thousandths place to determine whether to round up or down the digit in the thousandths place. In this case, rounding 245.2678 to the nearest thousandth, the digit in the ten-thousandths place is 6, which is greater than or equal to 5, so you would round up the digit in the thousandths place. Therefore, the correct answer is the ten-thousandths place. Choices B, C, and D are incorrect because they do not directly influence the rounding of the thousandths place in this scenario.

Correct Answer: A

Rationale: To simplify the expression (x^2 + 2x)/(x), we factor out x from the numerator to get x(x + 2) and then cancel the x in the denominator. This simplifies to x + 2, making choice A the correct answer. Choice B (x^2 + 2) is incorrect as it does not account for the division by x. Choice C (x(x + 2)) is also incorrect as it represents the factored form before cancellation. Choice D (1 + 2/x) is incorrect as it does not simplify the expression correctly.

Correct Answer: B

Rationale: To find the volume of a cube, you cube the length of one side. In this case, the side length is 3 cm, so the volume is calculated as 3 cm * 3 cm * 3 cm = 27 cm³. Therefore, the correct answer is 27 cm³. Choice A (9 cm³), Choice C (18 cm³), and Choice D (12 cm³) are incorrect as they do not correctly calculate the volume of a cube with a side length of 3 cm.

Correct Answer: D

Rationale: To convert a decimal to a percent, you multiply by 100. Therefore, 0.80 * 100 = 80%. The correct answer is D. Choice A (40%) is incorrect as 0.80 is not equivalent to 40%. Choice B (125%) is incorrect as it is greater than 100%. Choice C (90%) is incorrect as it does not reflect the correct conversion of 0.80 to a percent.

Correct Answer: A

Rationale: The mode of a set of numbers is the value that appears most frequently. In the given set {4, 4, 5, 7, 8}, the number 4 appears twice, which is more frequent than any other number. Therefore, the mode of this set is 4. Choice B, 5, is incorrect as it only appears once in the set. Choices C and D, 7 and 8 respectively, also appear only once each, making them less frequent than the number 4.

Correct Answer: A

Rationale: To round 8.067 to the nearest tenth, you look at the digit in the hundredth place, which is 6. Since 6 is equal to or greater than 5, you round up the digit in the tenth place. Therefore, 8.067 rounded to the nearest tenth is 8.1. Choice B (8.1) is incorrect as it duplicates the correct answer. Choice C (8) is incorrect as it does not account for the decimal part. Choice D (8.11) is incorrect as it rounds the number to the nearest hundredth, not the nearest tenth.

Correct Answer: A

Rationale: To find 15% of 200, you multiply 0.15 by 200, which equals 30. Therefore, the correct answer is A. Choice B (20) is incorrect because it represents 10% of 200. Choice C (25) is incorrect as it does not accurately represent 15% of 200. Choice D (40) is incorrect as it represents 20% of 200.