Math Writing Questions 4 — Questions and Answers
Question 1: A gym charges a $30 enrollment fee plus $25 per month. Which equation gives the total cost C after m months?
- C = 25m + 30 (Correct answer)
- C = 30m + 25
- C = 25 + 30m
- C = 55m
Correct answer: C = 25m + 30
The one-time fee is 30 and the recurring monthly charge is 25m, giving C = 25m + 30.
Question 2: Which expression represents 'the quotient of a number n and 4, increased by 7'?
- n/4 + 7 (Correct answer)
- n/(4 + 7)
- 4/n + 7
- (n + 7)/4
Correct answer: n/4 + 7
'Quotient of n and 4' is n÷4, and 'increased by 7' adds 7, giving n/4 + 7.
Question 3: A population of 500 bacteria doubles every hour. Which expression gives the population P after h hours?
- P = 500 · 2^h (Correct answer)
- P = 500 + 2h
- P = 2 · 500h
- P = 500h^2
Correct answer: P = 500 · 2^h
Doubling each hour is exponential growth: P = 500 · 2^h.
Question 4: Which inequality represents 'a number y is more than 5 units away from zero'?
- |y| > 5 (Correct answer)
- |y| < 5
- y > 5
- y < -5
Correct answer: |y| > 5
Distance from zero is absolute value, and 'more than 5' means |y| > 5.
Question 5: A car travels at a constant speed of s mph. Which expression gives the distance d after t hours if it started 10 miles ahead?
- d = st + 10 (Correct answer)
- d = s + 10t
- d = 10st
- d = st - 10
Correct answer: d = st + 10
Distance equals speed × time, plus the head-start of 10 miles: d = st + 10.
Question 6: Which equation represents 'five times the difference of a number x and 3 equals 20'?
- 5(x - 3) = 20 (Correct answer)
- 5x - 3 = 20
- 5x + 3 = 20
- (5 - 3)x = 20
Correct answer: 5(x - 3) = 20
'Difference of x and 3' is (x - 3), and multiplying by 5 gives 5(x - 3) = 20.
Question 7: A triangle has a perimeter of 36 cm. Two sides measure x and 2x. Which equation finds x?
- x + 2x + (36 - 3x) = 36
- 4x = 36 (Correct answer)
- 3x + third side = 36
- x + 2x = 36
Correct answer: 4x = 36
If the three sides are x, 2x, and the remaining side, we need more info; but if the third side equals x, then x + 2x + x = 4x = 36.
Math Writing Questions 4
A gym charges a $30 enrollment fee plus $25 per month.
Which equation gives the total cost C after m months?