Solve for x: x/5 = 3/10.
- A. x = 0.6
- B. x = 0.6
- C. x = 0.9
- D. x = 1.5
Correct Answer: D
Rationale: To solve for x when x/5 = 3/10, you need to cross-multiply. This gives you 10x = 5 3. Simplifying further, you get x = 15/10, which reduces to x = 1.5. Therefore, the correct answer is x = 1.5. Choices A, B, and C are incorrect because they do not match the correct calculation for x.
You may also like to solve these questions
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.
A marathon runner is training for her next race. On her weekly weekend run she completes 21.4 miles and burns 2276 calories. What is her rate of calories burned per mile?
- A. 106.4
- B. 105.6
- C. 107.5
- D. 109.3
Correct Answer: A
Rationale: To calculate the rate of calories burned per mile, divide the total calories burned by the total miles run: 2276 · 21.4 ≈ 106.4 calories per mile. The correct answer is A. Choice B, C, and D are incorrect as they do not match the correct calculation result. Therefore, they can be eliminated. It is essential to divide the total calories burned by the total miles run to determine the rate of calories burned per mile accurately.
How many pounds are in 128 ounces?
- A. 16 pounds
- B. 10 pounds
- C. 12 pounds
- D. 8 pounds
Correct Answer: D
Rationale: The correct answer is D, 8 pounds. There are 16 ounces in a pound. To convert 128 ounces to pounds, you divide 128 by 16, which equals 8 pounds. Choice A, 16 pounds, is incorrect because that would be the conversion the other way around, from pounds to ounces. Choices B and C are incorrect as they do not reflect the correct conversion from ounces to pounds.
How many milliliters are in 6 liters?
- A. 60 milliliters
- B. 6000 milliliters
- C. 600 milliliters
- D. 0.6 milliliters
Correct Answer: B
Rationale: The correct answer is B: 6000 milliliters. There are 1,000 milliliters in a liter. To convert liters to milliliters, you multiply the number of liters by 1,000. Therefore, 6 liters = 6 1,000 = 6,000 milliliters. Choices A, C, and D are incorrect because they do not correctly convert liters to milliliters.
Convert 5/8 to a decimal.
- A. 0.625
- B. 0.5
- C. 0.4
- D. 0.75
Correct Answer: A
Rationale: To convert 5/8 to a decimal, divide 5 by 8: 5 · 8 = 0.625. The correct answer is A (0.625). Choice B (0.5) is incorrect because it represents 1/2. Choice C (0.4) is incorrect because it represents 2/5. Choice D (0.75) is incorrect because it represents 3/4.