Let, n is the number of rides at which he pays same in both the deal.
Deal 1 :
Amount paid, A = $36 .
Deal 2 :
Amount paid, A = 14 + 2n
Equating both the equation, we get :
14 + 2n = 36
2n = 22
n = 11
Therefore, at a cost of $36 and at 11 rides both the deals are same.
Hence, this is the required solution.