There are 6,657 marbles in a jar. Approximately 34% are white, and the rest are black. How many black marbles are there?
- A. 4,394
- B. 4,000
- C. 3,000
- D. 5,000
Correct Answer: A
Rationale: To find the number of black marbles, we need to calculate the percentage that represents the black marbles, which is 100% - 34% = 66%. Then, we find 66% of 6,657 to determine the number of black marbles. 66% of 6,657 is approximately 4,394, so there are 4,394 black marbles in the jar. Choice A is correct. Choices B, C, and D are incorrect as they do not reflect the correct calculation for the number of black marbles in the jar.
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Which of the following numbers is a perfect square?
- A. 10
- B. 12
- C. 15
- D. 16
Correct Answer: D
Rationale: A perfect square is a number obtained by squaring an integer. In this case, 16 is a perfect square because it is the result of squaring 4 (4 x 4 = 16). The other answer choices, 10, 12, and 15, are not the product of squaring any whole number, making them incorrect. Therefore, the correct answer is 16, as it is a perfect square.
Convert the fraction 7/8 into a decimal and percent.
- A. Decimal: 0.875, Percent: 87.5%
- B. Decimal: 0.78, Percent: 78%
- C. Decimal: 0.88, Percent: 88%
- D. Decimal: 0.90, Percent: 90%
Correct Answer: A
Rationale: To convert the fraction 7/8 into a decimal, you divide 7 by 8, which equals 0.875. To express this decimal as a percentage, you multiply it by 100 to get 87.5%. Choices B, C, and D are incorrect because they do not represent the correct conversion of the fraction 7/8 into a decimal and a percent.
If 1 pound equals 453.59 grams, how many grams would a 7 lb. baby weigh?
- A. 3175.13 grams
- B. 4000 grams
- C. 4535 grams
- D. 3500 grams
Correct Answer: A
Rationale: To convert pounds to grams, multiply the weight in pounds by the conversion factor of 453.59 grams per pound. Therefore, 7 pounds x 453.59 grams/pound = 3175.13 grams, which is the weight of a 7 lb. baby in grams. Choice A is correct. Choice B (4000 grams) is incorrect as it does not use the correct conversion factor. Choice C (4535 grams) is incorrect as it seems to have used a rounding error. Choice D (3500 grams) is incorrect as it does not apply the correct conversion factor.
A baseball team won 72 games. This was 90% of the games it played. How many games did it play?
- A. 75
- B. 80
- C. 85
- D. 100
Correct Answer: B
Rationale: Let the total number of games be x. If the team won 72 games, which is 90% of the total games played, we can set up the equation: 72 = 0.90 * x. To find x, divide 72 by 0.90: x = 72 / 0.90 = 80 games. Therefore, the baseball team played 80 games in total. Choice A, 75, is incorrect because it is less than 80. Choice C, 85, is incorrect as it is more than 80. Choice D, 100, is incorrect as it is significantly more than the calculated total of 80 games.
The physician ordered 16 mg of Ibuprofen per kg of body weight; on hand are 80 mg tablets. The child weighs 15 kg. How many tablets will you give?
- A. 3 tablets
- B. 2 tablets
- C. 1 tablet
- D. 2.5 tablets
Correct Answer: B
Rationale: To calculate the total dose required for the child, multiply the child's weight (15 kg) by the prescribed dose per kg (16 mg/kg): 15 kg * 16 mg/kg = 240 mg. Next, determine how many tablets are needed to reach this total dose: 240 mg / 80 mg per tablet = 3 tablets. However, since you cannot give a fraction of a tablet, the correct answer is 2 tablets. Choice A is incorrect because it miscalculates the number of tablets needed. Choice C is incorrect because only 1 tablet is not sufficient to reach the required dose. Choice D is incorrect because you cannot give a partial tablet, so it has to be rounded down to the nearest whole tablet.
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