Question

In the first three days of its launch, the Galaxy Music Store sold 14 CDs of album x, 8 of album y, and 6 of album z through Branch A. Through Branch B, the store sold 7 CDs of album x, 13 of album y, and 4 of album z. Branch C sold 2 CDs of album x, 11 of album y, and 1 of album z. The total sales from each branch were as follows: Branch A: $166, Branch B: $145, Branch C: $84. What is the price of album y?

Answer 1

The price of album y is $5.80. I solved the system of equations of B and C. Getting rid of the variable z, I was able to get rid of x next. Solving this system gave me $5.80 without having to substitute into the other equation.