Solve for y if y = 3: 4y + 21/y
- A. 19
- B. 7.7
- C. 23/3
- D. 11
Correct Answer: A
Rationale: To solve the expression 4y + 21/y when y = 3, substitute y = 3: 4 * 3 + 21 / 3 = 12 + 7 = 19. Therefore, the correct answer is 19. Choice A, '19,' is the correct result of the expression when y = 3. Choice B, '7.7,' is incorrect as the correct answer is an integer, not a decimal. Choice C, '23/3,' is incorrect as it is not the simplified integer result of the expression. Choice D, '11,' is incorrect as it does not result from the given expression when y = 3.
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If a train travels at 80 kilometers per hour, how many kilometers will it travel in 3 hours?
- A. 240 kilometers
- B. 160 kilometers
- C. 240 kilometers
- D. 210 kilometers
Correct Answer: A
Rationale: To find the total distance traveled, you need to multiply the speed of the train by the time it travels. So, 80 km/h * 3 hours = 240 kilometers. Therefore, the correct answer is 240 kilometers. Choice B (160 kilometers) is incorrect because it is the result of multiplying the speed by 2 hours instead of 3. Choice C (240 kilometers) is the same as the correct answer, making it redundant. Choice D (210 kilometers) is incorrect as it is the result of multiplying the speed by 2.5 hours instead of 3.
Solve for x: x/250 = 3/500
- A. 1.5
- B. 25.5
- C. 1500
- D. 2.5
Correct Answer: A
Rationale: To solve for x in the equation x/250 = 3/500, you can cross-multiply: x*500 = 3*250. Therefore, 500x = 750. Now, divide both sides by 500: x = 750/500. Simplifying, x = 1.5. Therefore, the correct answer is A, 1.5. Choice B, 25.5, is incorrect as it does not match the correct calculation. Choice C, 1500, is incorrect as it is not the result of solving the equation given. Choice D, 2.5, is incorrect as well, as it does not align with the correct value of x obtained from the equation.
A marathon runner completes 21.6 miles and burns 2,274 calories. What is the rate of calories burned per mile?
- A. 105.28
- B. 105.37
- C. 105.45
- D. 105.55
Correct Answer: A
Rationale: To find the rate of calories burned per mile, you divide the total calories burned by the total miles run: 2274 calories / 21.6 miles = 105.28 calories per mile. Therefore, the correct answer is A. Choices B, C, and D are incorrect as they do not match the calculated value. The rate of calories burned per mile is a precise calculation based on the given values, and only choice A aligns with the correct calculation.
A baker can bake 4 cakes with 10 cups of sugar. If he has a 30-cup bag that is half full, how many cakes can he bake?
- A. 6 cakes
- B. 5 cakes
- C. 7 cakes
- D. 8 cakes
Correct Answer: A
Rationale: If the 30-cup bag is half full, it contains 15 cups of sugar. Since 10 cups are needed to bake 4 cakes, the baker can bake 4 * (15 / 10) = 6 cakes. Therefore, the correct answer is 6 cakes. Choice B, 5 cakes, is incorrect as it does not consider the correct sugar-to-cake ratio. Choices C and D are incorrect as they do not accurately calculate the number of cakes based on the available sugar.
If Alice consumes twice as many calories as Claire, and Claire consumes 2,500 calories a day, how many calories does Alice consume per week?
- A. 17,500
- B. 15,000
- C. 22,500
- D. 35,000
Correct Answer: D
Rationale: If Claire consumes 2,500 calories a day, Alice, consuming twice as many calories as Claire, would consume 2 * 2,500 = 5,000 calories per day. To find out how many calories Alice consumes per week, we multiply her daily consumption by 7 (days in a week): 5,000 * 7 = 35,000 calories. Therefore, Alice consumes 35,000 calories per week. Choices A, B, and C are incorrect because they do not account for Alice consuming twice as many calories as Claire.