Nokea
Subtract 15 3/4 - 8 2/5.
- A. 7 7/20
- B. 6 7/20
- C. 9 1/5
- D. 8 2/5
Correct Answer: A
Rationale: To subtract mixed numbers, find a common denominator. In this case, the common denominator is 20. Convert 15 3/4 to 15 15/20. Then, subtract 15 15/20 - 8 8/20 = 7 7/20. Therefore, the correct answer is A. Choice B is incorrect as it does not match the result of the subtraction. Choice C is incorrect as it is not the result of the subtraction. Choice D is incorrect as it represents the second number being subtracted, not the result of the subtraction.
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A man can type 45 words per minute. How many words can he type in 20 minutes?
- A. 875 words
- B. 800 words
- C. 900 words
- D. 875 words
Correct Answer: C
Rationale: To calculate the total number of words typed in 20 minutes, multiply the typing speed per minute (45 words) by the duration in minutes (20 minutes): 45 words/min 20 min = 900 words. Therefore, the correct answer is 900 words. Choices A, B, and D are incorrect because they do not reflect the accurate calculation based on the given information.
A train leaves the station at 1:45 PM traveling at a constant speed of 65 mph. If it arrives at its destination at 3:15 PM, how many miles did it travel?
- A. 97.5 miles
- B. 100 miles
- C. 95 miles
- D. 105 miles
Correct Answer: A
Rationale: To calculate the distance traveled by the train, multiply the speed (65 mph) by the time it took to reach the destination, which is 1.5 hours (3:15 PM - 1:45 PM = 1.5 hours). Therefore, 65 mph 1.5 hours = 97.5 miles. This calculation is correct because distance = speed time. Choices B, C, and D are incorrect as they do not reflect the correct calculation based on the given information.
You need to buy cardboard to cover a rectangular box with dimensions 40cm by 30cm by 25cm. Considering only the exterior surfaces (not flaps or openings), how much cardboard do you need (assume one sheet covers 0.5 sq m)?
- A. 0.3 sq m
- B. 0.6 sq m
- C. 1.2 sq m
- D. 1.8 sq m
Correct Answer: C
Rationale: To find the total surface area of the rectangular box, calculate the area of each side and sum them up. The areas of the sides are: 2(40x30) + 2(40x25) + 2(30x25) = 2400 + 2000 + 1500 = 5900 sq cm. Convert this to square meters by dividing by 10,000: 5900/10,000 = 0.59 sq m. Since one sheet covers 0.5 sq m, you would need 2 sheets to cover the box fully, which equals 1 sq m. Therefore, the correct answer is 1.2 sq m. Choice A (0.3 sq m) is too small for the dimensions provided. Choice B (0.6 sq m) is incorrect as it doesn't match the calculated surface area. Choice D (1.8 sq m) is too high for the surface area of the box.
How many chickens are needed to produce 24 eggs in 24 hours if it takes 2 chickens to produce 6 eggs in 24 hours?
- A. 8 chickens
- B. 12 chickens
- C. 18 chickens
- D. 6 chickens
Correct Answer: A
Rationale: To produce 24 eggs in 24 hours, 4 times the number of chickens needed to produce 6 eggs is required. Since it takes 2 chickens to produce 6 eggs, 8 chickens are needed to produce 24 eggs in the same time frame. Choice B, 12 chickens, is incorrect because it doesn't consider the proportionality between chickens and eggs. Choice C, 18 chickens, is incorrect as it overestimates the number of chickens needed. Choice D, 6 chickens, is incorrect as it doesn't account for the increased number of eggs required.
How many pounds are in 48 ounces?
- A. 3 lbs
- B. 6 lbs
- C. 4 lbs
- D. 8 lbs
Correct Answer: A
Rationale: To convert ounces to pounds, you need to know that there are 16 ounces in a pound. Therefore, to find out how many pounds are in 48 ounces, you divide 48 by 16: 48 · 16 = 3 pounds. This means that 48 ounces is equivalent to 3 pounds. Choice B, 6 lbs, is incorrect as it doesn't correctly convert 48 ounces to pounds. Choice C, 4 lbs, is incorrect as it doesn't take into account the conversion factor of 16 ounces per pound. Choice D, 8 lbs, is also incorrect as it doesn't reflect the accurate conversion of ounces to pounds.