Equation of question

Question

Mr.Akika has 43 18-cent and 32-cent stamps all total. The stamps are worth $11.66. How many of each kind of stamp does he have?

Answer 1

Let x is number of 18-cent stamps and y is number of 32-cent stamps.

Then we have system of equations: x + y = 43

18x + 32y = 1166

Let multiply 1st equation by -18 and adding to 2nd equation we get: 32y - 18y = 1166 - 43·18, 14y = 392,

y = 392/14 = 28, x = 43 - 28 = 15

Answer: 15 18-cent stamps, 28 32-cent stamps