Nokea
Solve for x: 2x - 7 = 9.
- A. x = 10
- B. x = 7
- C. x = 8
- D. x = 5
Correct Answer: C
Rationale: To solve the equation 2x - 7 = 9, first, add 7 to both sides to isolate the variable: 2x = 16. Then, divide by 2 to solve for x: x = 8. Choice A (x = 10) is incorrect because the solution is x = 8, not 10. Choice B (x = 7) is incorrect as it does not correctly solve the equation. Choice D (x = 5) is incorrect as it does not yield the correct solution for x.
You may also like to solve these questions
Solve for x: x/5 = 3/10.
- A. x = 0.6
- B. x = 0.6
- C. x = 0.9
- D. x = 1.5
Correct Answer: D
Rationale: To solve for x when x/5 = 3/10, you need to cross-multiply. This gives you 10x = 5 3. Simplifying further, you get x = 15/10, which reduces to x = 1.5. Therefore, the correct answer is x = 1.5. Choices A, B, and C are incorrect because they do not match the correct calculation for x.
A marathon runner is training for her next race. On her weekly weekend run she completes 21.4 miles and burns 2276 calories. What is her rate of calories burned per mile?
- A. 106.4
- B. 105.6
- C. 107.5
- D. 109.3
Correct Answer: A
Rationale: To calculate the rate of calories burned per mile, divide the total calories burned by the total miles run: 2276 · 21.4 ≈ 106.4 calories per mile. The correct answer is A. Choice B, C, and D are incorrect as they do not match the correct calculation result. Therefore, they can be eliminated. It is essential to divide the total calories burned by the total miles run to determine the rate of calories burned per mile accurately.
A train travels at 70 mph for 6 hours. How far did it travel?
- A. 490 miles
- B. 490 miles
- C. 540 miles
- D. 420 miles
Correct Answer: D
Rationale: To find the distance traveled, multiply the speed of 70 mph by the time of 6 hours: 70 mph 6 hours = 420 miles. Therefore, the correct answer is 420 miles. Choices A, B, and C are incorrect as they do not result from the correct calculation.
A man can type 45 words per minute. How many words can he type in 20 minutes?
- A. 875 words
- B. 800 words
- C. 900 words
- D. 875 words
Correct Answer: C
Rationale: To calculate the total number of words typed in 20 minutes, multiply the typing speed per minute (45 words) by the duration in minutes (20 minutes): 45 words/min 20 min = 900 words. Therefore, the correct answer is 900 words. Choices A, B, and D are incorrect because they do not reflect the accurate calculation based on the given information.
Subtract 12 - 7 4\5.
- A. 5 1\5
- B. 5 2\5
- C. 4 5\6
- D. 3 1\3
Correct Answer: A
Rationale: Subtract the whole numbers and then subtract the fractions: 12 - 7 4\5 = 5 1\5.