The least common multiple (LCM) of two numbers is the smallest number that is a multiple of both. Which of the following represents the LCM of 14 and 21?
- A. 42
- B. 63
- C. 84
- D. 168
Correct Answer: C
Rationale: Rationale:
To find the least common multiple (LCM) of 14 and 21, we need to determine the smallest number that is a multiple of both 14 and 21.
First, list the multiples of 14: 14, 28, 42, 56, 70, 84, ...
Next, list the multiples of 21: 21, 42, 63, 84, ...
The smallest number that appears in both lists is 42. Therefore, the LCM of 14 and 21 is 42.
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What is the result of dividing 3.44 by 0.6 rounded off to the nearest whole number?
- B. 6
- C. 11
- D. 2
Correct Answer: B
Rationale: To find the result of dividing 3.44 by 0.6, you perform the division operation: 3.44 · 0.6 = 5.73. When rounded off to the nearest whole number, 5.73 becomes 6. Therefore, the correct answer is 6. Choice A is incorrect as the result is not 0. Choice C is incorrect as it is not the closest whole number to 5.73. Choice D is incorrect as it does not reflect the accurate division result.
What is the perimeter of a garden bed with a side length of 8 meters?
- A. 16m
- B. 24m
- C. 32m
- D. 64m
Correct Answer: B
Rationale: The correct answer is B: 24m. The perimeter of a square is found by adding up all its sides. In this case, since the garden bed has a side length of 8 meters, the perimeter would be 8m + 8m + 8m + 8m = 24m. Choices A, C, and D are incorrect because they do not correctly calculate the perimeter of a square with a side length of 8 meters.
A hospital receives a shipment of vitamin tablets. The hospital ordered 6,000 tablets, but the shipment included 1/5 more tablets than the hospital ordered. How many tablets were in the shipment?
- A. 7,200 tablets
- B. 5,000 tablets
- C. 6,500 tablets
- D. 8,000 tablets
Correct Answer: A
Rationale: To find the total tablets in the shipment, first, calculate 1/5 of 6,000: 6,000 * 1/5 = 1,200. Add this to the original order: 6,000 + 1,200 = 7,200 tablets. Therefore, the shipment included 7,200 tablets. Choice B, 5,000 tablets, is incorrect because it does not account for the additional 1/5 of the original order. Choice C, 6,500 tablets, is incorrect as it only considers the original order and not the extra tablets. Choice D, 8,000 tablets, is incorrect as it overestimates the total by not considering the 1/5 more tablets included in the shipment.
Reduce 5 & 3/4 divided by 1/2.
- A. 5 & 1/2
- B. 2 & 3/8
- C. 18
- D. 11 & 1/2
Correct Answer: D
Rationale: To divide mixed numbers, convert them to improper fractions. 5 & 3/4 = 23/4 and 1/2 = 2/1. So, 23/4 · 2/1 = 23/4 * 1/2 = 23/8 = 2 & 7/8. Therefore, 5 & 3/4 divided by 1/2 reduces to 11 & 1/2. Choices A, B, and C are incorrect because they do not represent the correct result of dividing 5 & 3/4 by 1/2.
What is the result of adding 12 1/21 and 3 1/3?
- A. 15 8/21
- B. 16 5/24
- C. 15
- D. 14
Correct Answer: A
Rationale: To add 12 1/21 and 3 1/3, first add the whole numbers: 12 + 3 = 15. Then, add the fractions: 1/21 + 1/3. To find a common denominator, multiply 21 by 3 to get 63. Convert 1/21 to an equivalent fraction with a denominator of 63 by multiplying the numerator and denominator by 3, resulting in 3/63. Now add 3/63 (equivalent to 1/21) and 21/63 (equivalent to 1/3) to get 24/63. Simplifying 24/63 gives 8/21. Therefore, the sum is 15 8/21. Choices B, C, and D are incorrect because they do not result from the correct addition of the given numbers and fractions.