Question

The cost of item A is $8 and the

cost of item B is $4. You sold a
combined total of 13 of these items
and made $88. How much of each
item did you sell?

Answer 1

Answer: the number of item A that you sold is 11

the number of item B that you sold is 2

Explanation:

Let x represent the number of item A that you sold.

Let y represent the number of item B that you sold.

The total number of item A and item B sold is 13. This means that

x + y = 13

The cost of item A is $8 and the

cost of item B is $4. The total amount if money made is $88. This means that

8x + 4y = 88 - - - - - - - - - -1

Substituting x = 13 - y into equation 1, it becomes

8(13 - y) + 4y = 88

104 - 8y = 88

8y = 104 - 88 = 16

y = 16/8 = 2

x = 13 - y = 13 - 2 = 11

Answer 2

4 of item A, and 9 of item B

Explanation:

Let x represent the number of item sold in A

Let y represent the number of item sold in B

If the total number of item sold is 13. This implies

x + y = 13

The cost of item A is $8, the cost of item B is $4 and if the total amount of money made is $88, this implies

8(x) + 4(y) = 88 (Substitue x = 13 - y)

→ 8(13 - y) + 4y = 88

→ 104 - 8y + 4y = 88

→ 4y = 16

→ y = 4

If y = 4, then x = 13 - y = 9