Math Writing Questions 5 — Questions and Answers
Question 1: A runner completes a race in t minutes. A second runner finishes 8 minutes faster. Which expression gives the second runner's time?
- t - 8 (Correct answer)
- t + 8
- 8t
- t/8
Correct answer: t - 8
'Faster' means less time, so the second runner's time is t - 8.
Question 2: Which equation represents 'half of a number increased by 9 is 21'?
- n/2 + 9 = 21 (Correct answer)
- n/2 - 9 = 21
- (n + 9)/2 = 21
- 2n + 9 = 21
Correct answer: n/2 + 9 = 21
'Half of n' is n/2, and 'increased by 9' gives n/2 + 9 = 21.
Question 3: A vendor sells apples for $0.50 each and oranges for $0.75 each. Which expression gives the total cost for a apples and g oranges?
- 0.50a + 0.75g (Correct answer)
- 0.75a + 0.50g
- (0.50 + 0.75)(a + g)
- 1.25(a + g)
Correct answer: 0.50a + 0.75g
Multiply each item's price by its quantity and add: 0.50a + 0.75g.
Question 4: Which inequality represents 'the product of 3 and a number x is no less than 15'?
- 3x ≥ 15 (Correct answer)
- 3x ≤ 15
- 3x > 15
- 3x < 15
Correct answer: 3x ≥ 15
'No less than' means 'greater than or equal to,' so 3x ≥ 15.
Question 5: A pool is being filled at 8 gallons per minute and simultaneously drained at 3 gallons per minute. Which expression gives the net gallons after m minutes?
- 5m (Correct answer)
- 11m
- 8m
- 3m
Correct answer: 5m
Net fill rate is 8 - 3 = 5 gallons per minute, so the net gallons after m minutes is 5m.
Question 6: Which expression represents 'the square of the sum of x and 4'?
- (x + 4)² (Correct answer)
- x² + 4
- x² + 16
- x + 4²
Correct answer: (x + 4)²
'The sum of x and 4' is (x + 4), and squaring it gives (x + 4)².
Question 7: A phone plan costs $40 per month plus $0.10 per text message. If a user sends t texts and has a $55 budget, which inequality must hold?
- 40 + 0.10t ≤ 55 (Correct answer)
- 40 + 0.10t ≥ 55
- 0.10t ≤ 55
- 40t + 0.10 ≤ 55
Correct answer: 40 + 0.10t ≤ 55
Total cost 40 + 0.10t must not exceed the $55 budget, so 40 + 0.10t ≤ 55.
Math Writing Questions 5
A runner completes a race in t minutes.
A second runner finishes 8 minutes faster.
Which expression gives the second runner's time?