Question

The number of sit-ups Micah does is the sum of twice a number and 25. The number of sit-ups Micah does is also 3 times the number minus 25. How

many sit-ups does Micah do? (hint: set up two equations, then solve for each variable)

Answer 1

Answer: 125

Explanation:

Let the number represented in the question be b.

Let the number of situps be also represented by z.

The number of sit-ups Micah does is the sum of twice a number and 25. This means:

z = (2×b) + 25

z = 2b + 25...... equation i

The number of sit-ups Micah does is also 3 times the number minus 25. This means:

z = (3×b) - 25

z = 3b - 25 .......... equation ii

Equate equation I and ii together.

2b + 25 = 3b - 25

Collect like terms

3b - 2b = 25 + 25

b = 50

Put the value of back into equation I

z = 2b + 25

z = (2×50) + 25

z = 100 + 25

z = 125

The number of situps is 125.