Question

last month, a bookstore ran the following at and sold 85 calculators, generating $4,083 in sales. How many of each type of calculator do the bookstore sell?​

Answer 1

31 scientific calculators

54 graphing calculators

Explanation:

X = number of $15 calculators

Y = number of $67 calculators

X+Y = 85 then X = 85-Y

15X+67Y = 4083

substitute for X

15(85-Y)+67Y = 4083

1275 - 15Y + 67Y = 4083

reduce

52Y = 2808

Y = 54

X = 31