Question 704837
    A bookstore sold 85 calculators, generating $3,875 in sales. Two kinds of calculators were sold at $15 and $67. How many of each were sold?
.
Let x = number of $15 calculators sold
then
85-x = number of $67 calculators sold
.
15x + 67(85-x) = 3875
15x + 5695-67x = 3875
5695-52x = 3875
-52x = -1820
x = 35 (number of $15 calculators)
.
Number of $67 calculators:
85-x = 85-35 = 50