Question

a membership at a gym cost 15 dollars a person without a membership must pay 1.75 each time they go to the gym how many time will a person have to go to make the membership a better deal

Answer 1

We can use an inequality.
x = number of times one has to go.

1.75x > 15.00
1.75x / 1.75 > 15.00/1.75
x = 15.00 / 1.75
x > 8.57

So when x > 9 time the membership is a better deal.

Answer 2

On the 9th time it will be a better deal to have a membership. 9 times 1.75 is 15.75 which is more than 15