Question

The cost to join a gym includes a one-time membership fee, plus a monthly fee. John joined the gym and paid $325 for 6 months.Abigail joined the gym and paid $475 for 9 months.What is the monthly fee after a person joins the gym?

Answer 1

We need to construct the system of equations in order to solve that problem. Let's denote one-time membership fee with x and monthly fee with y. Then we can write that John paid x+6y=325 and Abigail paid x+9y=475. Solving the system of equations $\left \{ {{x+6y=325} \atop {x+9y=475}} \right.$, we find that x=25 and y=50. The monthly fee is 50 dollars.