A coffee wholesaler wants to make $200lb$ of a special blend by mixing three different types of coffee that sell for $$7,$$$7\mathrm{.}50$ and $$8$ per pound so as to sell the special blend at $$7\mathrm{.}62$ per pound. The wholesaler expects to make the same money by selling the blend, if the amount of the highest priced coffee is equal to combined amount of the other two types. How much of each type must be used in the blend?