john has a total of 18 stamps which consists of 25 cents and 2 cent stamps they have a value of $2.20 how many of each do you have?

Answer 1

x = 18 - y

.25x + .02y = 2.20

Substitute 18-y for x in the second equation and solve for y. Insert that value into the first equation to solve for x. Check by putting both values into the second equation.