First lets create an equation for each:
1) Cost = 5x + 60
2) Cost = 11x
Where x is the number of lessons.
Since we want to find the value of x (the number of lessons), we can set both equations equal to each other:
5x + 60 = 11x
Subtract 5x from both sides:
60 = 6x
Divide by 6:
x = 10
So it will take 10 lessons till a member and a nonmember pay the same amount.