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?

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.

Correct Answer: A

Rationale: To add fractions, find a common denominator, which in this case is 40. Convert each fraction to have the common denominator: 7/8 = 35/40, 9/10 = 36/40, and 6/5 = 48/40. Add these fractions to get 119/40. Simplify this improper fraction to a mixed number, which is 3 & 39/40. Choice B and C are incorrect as they do not represent the sum of the fractions. Choice D is incorrect; the whole number part should be 3, not 2.

Correct Answer: B

Rationale: To compare who ate more of their meal, we need to convert the fractions to the same format. John ate 75% of his lunch, which is equivalent to 3/4. Sally ate 5/8 of her lunch. Comparing 3/4 to 5/8, we find that 3/4 is greater than 5/8. Therefore, John ate more of his meal than Sally. Choice B, John, is the correct answer. Choices A, C, and D are incorrect because John consumed 3/4 of his lunch, which is more than 5/8 that Sally consumed, making him the one who ate more of his meal.

Correct Answer: A

Rationale: To subtract 2 5/8 from 7/8, first, convert 7/8 to an equivalent fraction with the same denominator as 2 5/8, which is 8. 7/8 equals 1 whole and 1/8. Subtracting 1 whole from 2 whole results in 1 whole, and subtracting 1/8 from 5/8 gives 4/8 or 1/2. Therefore, the answer is 1 1/2, which simplifies to 1 3/4. Choice B, 2, is incorrect as it doesn't represent the correct result of the subtraction. Choice C, 1, is incorrect as it doesn't account for the fractional part of the answer. Choice D, 2 & 1/2, is incorrect as it doesn't match the calculated result of 1 3/4.

Correct Answer: A

Rationale: To determine the amount of medication the patient should receive, divide the prescribed dose by the dose per mL in the vial. In this case, 5 mg · 2 mg/mL = 2.5 mL. Therefore, the patient should receive 2.5 mL of the medication. Choice B (2 mL) is incorrect because it does not reflect the correct calculation. Choice C (3 mL) is incorrect as it is higher than the actual amount calculated. Choice D (1 mL) is incorrect as it is lower than the actual amount calculated.

Correct Answer: B

Rationale: There are 1,000 milliliters in 1 liter. The prefix 'milli-' means one-thousandth, so when converting from liters to milliliters, you multiply by 1,000. Therefore, the correct answer is 1,000 mL. Choice A (100 mL) is incorrect as it represents one-tenth of the correct conversion. Choice C (500 mL) is incorrect as it is half of the correct conversion. Choice D (50 mL) is incorrect as it is one-twentieth of the correct conversion.

Correct Answer: C

Rationale: To convert grams to milligrams, you need to multiply by 1,000 since there are 1,000 milligrams in a gram. Therefore, 7 grams is equal to 7,000 milligrams. Choice A (700 mg) is incorrect because it represents grams to milligrams incorrectly. Choice B (0.7 mg) is incorrect as it converts grams to milligrams erroneously by decimal placement. Choice D (0.07) is incorrect as it converts grams to milligrams inaccurately by misplacing the decimal point.

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.

Correct Answer: A

Rationale: To convert a decimal to a percentage, you move the decimal point two places to the right and add a percentage sign. Therefore, 0.608 as a percent is 60.8%. The correct answer is A. Choice B (68%) is incorrect because it represents the percentage for a different decimal value. Choice C (0%) is incorrect as it represents 0 as a percentage, not 0.608. Choice D (6%) is incorrect as it also represents a different decimal value, not 0.608.