What is the result of adding 7/21 + 10/21?
- A. 17/21
- B. 15/21
- C. 9/21
- D. 10/21
Correct Answer: A
Rationale: When adding fractions with the same denominator, you simply add the numerators while keeping the denominator the same. In this case, 7/21 + 10/21 = 17/21. Therefore, the correct answer is A. Choice B (15/21) is incorrect because it adds the numerators incorrectly. Choice C (9/21) is incorrect as it does not reflect the sum of the fractions provided. Choice D (10/21) is also incorrect as it does not represent the correct sum of the two fractions.
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A kite has a top base of 20cm, a bottom base of 30cm, and two equal side lengths of 15cm. What is its perimeter?
- A. 55cm
- B. 65cm
- C. 70cm
- D. 80cm
Correct Answer: C
Rationale: To find the perimeter of a kite, you need to add the lengths of all its sides. In this case, the perimeter is calculated as the sum of the top base, bottom base, and twice the side length. Therefore, perimeter = top base + bottom base + 2 * side length = 20cm + 30cm + 2 * 15cm = 70cm. Choice A, B, and D are incorrect as they do not consider all sides of the kite in the calculation.
You need 4/5 cups of water for a recipe. You accidentally put 1/3 cups into the mixing bowl with the dry ingredients. How much more water in cups do you need to add?
- A. 7/15 cups
- B. 2/3 cups
- C. 1/3 cups
- D. 1/15 cups
Correct Answer: A
Rationale: To find how much more water is needed, subtract 1/3 cup from 4/5 cup. First, find a common denominator:
The least common denominator between 5 and 3 is 15. Convert the fractions: 4/5 = 12/15, 1/3 = 5/15. Now, subtract: 12/15 - 5/15 = 7/15. Therefore, you need to add 7/15 cups of water. Choice B (2/3 cups) is incorrect because it does not represent the correct amount of additional water needed. Choice C (1/3 cups) is incorrect because this is the amount of water that was accidentally added. Choice D (1/15 cups) is incorrect as it does not reflect the correct calculation of the additional water required.
Convert 2100 to standard time.
- A. 12:00 PM
- B. 2:00 AM
- C. 9:00 PM
- D. 2:00 PM
Correct Answer: C
Rationale: Military time is based on a 24-hour clock. To convert 2100 hours to standard time, subtract 1200 from the time if it is greater than or equal to 1300. In this case, 2100 - 1200 = 900, which corresponds to 9:00 PM in standard time. Choice A, 12:00 PM, is incorrect because 2100 is in the evening, not noon. Choice B, 2:00 AM, is incorrect as it represents the early morning hours. Choice D, 2:00 PM, is incorrect as it is in the afternoon, not the evening.
Change the following percentage to a decimal: 0.03%
- A. 0.03
- B. 0.0003
- C. 0.3
- D. 0.003
Correct Answer: B
Rationale: To convert a percentage to a decimal, divide by 100. Therefore, 0.03% · 100 = 0.0003. The correct answer is B. Choice A (0.03) is incorrect because it does not account for the conversion of percentage to decimal. Choice C (0.3) is incorrect as it represents 0.03 as 30% rather than 0.03%. Choice D (0.003) is also incorrect as it does not accurately convert 0.03% to a decimal.
Three nurses worked 8-hour shifts. Nurse 1 monitored 6 patients during her shift. Nurse 2 monitored 8 patients, and Nurse 3 monitored 12 patients. How many patients were monitored in total?
- A. 26 patients
- B. 24 patients
- C. 20 patients
- D. 23 patients
Correct Answer: A
Rationale: To find the total number of patients monitored, add the patients monitored by each nurse: 6 (Nurse 1) + 8 (Nurse 2) + 12 (Nurse 3) = 26 patients. Therefore, the correct answer is 26 patients. Choice B (24 patients), Choice C (20 patients), and Choice D (23 patients) are incorrect as they do not correctly sum up the patients monitored by each nurse.