Solve for x: 3x - 5 = 10
- A. x = 5
- B. x = 10
- C. x = 15
- D. x = 20
Correct Answer: A
Rationale: To solve the equation 3x - 5 = 10, start by isolating x. Add 5 to both sides of the equation to get 3x = 15. Then, divide by 3 on both sides to find x = 5. Therefore, the correct answer is x = 5. Choice B, x = 10, is incorrect because adding 5 to 10 does not yield 10. Choice C, x = 15, is incorrect as adding 5 to 15 does not equal 10. Choice D, x = 20, is incorrect because adding 5 to 20 does not result in 10.
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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.
You have orders to administer 20 mg of a certain medication to a patient. The medication is stored at a concentration of 4 mg per 5-mL dose. How many milliliters will need to be administered?
- A. 30 mL
- B. 25 mL
- C. 20 mL
- D. 15 mL
Correct Answer: B
Rationale: To administer 20 mg of the medication, you would need 25 mL. This calculation is derived from the concentration of 4 mg per 5 mL. By setting up a proportion, you can determine that for 20 mg, 25 mL must be administered as follows: (20 mg / 4 mg) = (x mL / 5 mL). Solving for x results in x = 25 mL. Choice A is incorrect because it miscalculates the proportion. Choices C and D are incorrect as they do not account for the correct concentration of the medication.
A mother is planning a birthday party. She will give each child 15 balloons. There are 50 balloons per packet. How many packets does the mother need if there will be 16 children?
- A. 17
- B. 5
- C. 6
- D. 50
Correct Answer: B
Rationale: To calculate the total number of balloons needed, multiply the number of children by the balloons each child will receive: 16 children * 15 balloons = 240 balloons. Since there are 50 balloons per packet, divide the total number of balloons needed by the balloons per packet: 240 balloons · 50 balloons per packet = 4.8 packets. As you cannot buy a fraction of a packet, the mother will need to round up to the nearest whole number of packets, which is 5. Therefore, the correct answer is 5 packets. Choice A (17) is incorrect because it does not accurately calculate the number of packets needed. Choice C (6) is incorrect as it overestimates the number of packets required. Choice D (50) is incorrect as it does not consider the number of children and balloons per child in the calculation.
Convert to metric: 7 grams = x milligrams
- A. 700 mg
- B. 0.7 mg
- C. 7,000 mg
- D. 0.07
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.
Convert the following decimal to a percent: 0.0068
- A. 0.68
- B. 6.8
- C. 0.068
- D. 0.0068
Correct Answer: A
Rationale: To convert a decimal to a percent, move the decimal point two places to the right. Therefore, 0.0068 as a percentage is 0.68%. Choice A is correct because it represents the correct conversion. Choice B is incorrect as it would be the decimal 6.8 represented as a percentage. Choice C is incorrect as it would be the decimal 0.068 represented as a percentage. Choice D is incorrect as it is the original decimal value.
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