A shop spends $2400 to purchase a batch of basketballs and footballs. There are 15 more basketballs than footballs. The selling price of a basketball is 20% higher than that of a football. The selling price of each football is $60.
(a) Find the selling price of each basketball.
(b) If all the basketballs and footballs are sold, and the overall profit is $660, how many basketballs and footballs has the shop sold?