A syringe holds 3ml of liquid. How many syringes are needed to measure 15ml of liquid?
- A. 3
- B. 5
- C. 7
- D. 9
Correct Answer: B
Rationale: Since each syringe holds 3ml of liquid, to measure 15ml of liquid, you would need to divide 15ml by 3ml/syringe. This calculation gives you 5 syringes needed to measure 15ml of liquid. Choice A (3 syringes) is incorrect because 3 syringes would only hold 9ml of liquid, not 15ml. Choice C (7 syringes) and Choice D (9 syringes) are incorrect as they would result in an excess amount of liquid, which is not needed.
You may also like to solve these questions
How many milliliters are in 3 liters?
- A. 300 milliliters
- B. 3000 milliliters
- C. 1500 milliliters
- D. 300 milliliters
Correct Answer: B
Rationale: The correct answer is B: 3000 milliliters. There are 1,000 milliliters in a liter. Therefore, 3 liters = 3 1,000 = 3,000 milliliters. Choice A (300 milliliters) is incorrect as it represents the conversion of 0.3 liters, not 3 liters. Choice C (1500 milliliters) is incorrect as it is halfway between the correct answer and a common mistake of confusing liters with milliliters. Choice D (300 milliliters) is incorrect as it is the conversion of 0.3 liters, not 3 liters.
Subtract 12 - 7 4\5.
- A. 5 1\5
- B. 5 2\5
- C. 4 5\6
- D. 3 1\3
Correct Answer: A
Rationale: Subtract the whole numbers and then subtract the fractions: 12 - 7 4\5 = 5 1\5.
If Kevin can wash 30 cars in 15 minutes, how many minutes will it take him to wash 100 cars?
- A. 50 minutes
- B. 55 minutes
- C. 30 minutes
- D. 45 minutes
Correct Answer: A
Rationale: To find out how many minutes Kevin will take to wash 100 cars, set up a proportion: 30 cars is to 15 minutes as 100 cars is to x minutes. Cross multiplying gives 30x = 1500. Solving for x, x = 1500 / 30 = 50. Therefore, it will take Kevin 50 minutes to wash 100 cars. Choice A is correct. Choice B, C, and D are incorrect as they do not correctly calculate the time needed 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.
What is the result of subtracting 9.99 from 12.02?
- A. 2.03
- B. 2.21
- C. 3.17
- D. 7.97
Correct Answer: A
Rationale: The correct subtraction is 12.02 - 9.99 = 2.03. Therefore, the correct answer is A. Choice B, 2.21, is incorrect as it does not result from the given subtraction. Choice C, 3.17, is also incorrect. Choice D, 7.97, is incorrect as well. Thus, A is the only correct answer.
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