I’m sure you can do this on a calculator just input 75 + 25/100.
..........................................
65+50x = 55x + 20
-50x -50
65=5x+20
- 20 - 20
55=5x
55/5= 5x/5
11=x
The solution represents that it 11 months will make both gyms the exact same price.
They are both in the thousands places
