Correct Answer: A

Rationale: 15\25 + 42\52 simplifies to 1 3\10.

Correct Answer: A

Rationale: To solve the equation 3x - 5 = 10, start by isolating x. Add 5 to both sides of the equation to get 3x = 15. Then, divide by 3 on both sides to find x = 5. Therefore, the correct answer is x = 5. Choice B, x = 10, is incorrect because adding 5 to 10 does not yield 10. Choice C, x = 15, is incorrect as adding 5 to 15 does not equal 10. Choice D, x = 20, is incorrect because adding 5 to 20 does not result in 10.

Correct Answer: A

Rationale: To determine how much each friend paid, divide the total bill amount by the number of friends. In this scenario, $120 · 8 friends = $15. Therefore, each friend paid $15. Choice B ($10) is incorrect because dividing $120 by 8 does not yield $10. Choice C ($12) is incorrect because dividing $120 by 8 does not yield $12. Choice D ($20) is incorrect because dividing $120 by 8 does not yield $20.

Correct Answer: B

Rationale: 1 milliliter is approximately equal to 0.2 teaspoons. To find out how many teaspoons are in 0.8 milliliters, we can set up a proportion: 0.8 milliliters * 0.2 teaspoons/1 milliliter = 0.16 teaspoons. Since 0.16 teaspoons is not one of the answer choices, we need to convert it to a more practical measurement. The closest option is 0.4 teaspoons, making it the correct answer. Choice A, 0.2 teaspoons, is incorrect because 0.8 milliliters is more than that. Choices C and D, 0.6 teaspoons and 0.8 teaspoons, respectively, are also incorrect based on the conversion factor of 1 milliliter to 0.2 teaspoons.

Correct Answer: B

Rationale: To find the total cost, first calculate the cost of pens and staplers separately. 240 pens require 40 packs (240 pens · 6 pens per pack = 40 packs). Each pack of pens costs $2.35, so 40 packs cost $94 (40 packs $2.35 per pack = $94). For the staplers, 6 staplers require 3 packs (6 staplers · 2 staplers per pack = 3 packs). Each pack of staplers costs $12.95, so 3 packs cost $38.85 (3 packs $12.95 per pack = $38.85). Adding the cost of pens and staplers together gives a total of $132.85, which rounds to $132.00. Therefore, the correct answer is $132.00. Choice A is incorrect as it does not consider the individual prices of pens and staplers. Choice C is incorrect as it overestimates the total cost by combining the costs incorrectly. Choice D is incorrect as it underestimates the total cost by not considering both pens and staplers.