Correct Answer: D

Rationale: To find the product of 15 and 52, you simply multiply them together: 15 x 52 = 780. Therefore, the correct answer is 7.8. Choices A, B, and C are incorrect as they represent fractions or decimals much smaller than the correct product of 780.

Correct Answer: D

Rationale: The Roman numeral MDXVI translates to 1516 in Arabic numerals. The Roman numeral 'M' represents 1000, 'D' represents 500, 'X' represents 10, and 'VI' represents 6, which adds up to 1516. Therefore, the correct answer is 1516. Choices A, B, and C are incorrect as they do not match the Roman numeral MDXVI.

Correct Answer: B

Rationale: Geoff paid a total of 5 paperbacks x $0.35/paperback + 3 hardcover books x $50/hardcover book = $1.75 + $150 = $8.75. Since he gave the clerk a $10 bill, he received $10 - $8.75 = $1.25 change. However, since the options are in increments of $0.25, the closest amount is $0.75, so Geoff received $0.75 change. Option A is incorrect because it's not the closest amount to the actual change. Option C is incorrect as it represents the total change Geoff received, not the closest increment. Option D is incorrect as it overestimates the change Geoff received.

Correct Answer: C

Rationale: To find the sum of the digits of the number 72, you simply add the individual digits together: 7 + 2 = 9. Therefore, the sum of the digits is 9. Choice A (6), Choice B (5), and Choice D (7) are incorrect as they do not correctly sum up the individual digits of the number 72.

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.