Question

Abhasra and Aliyah are selling wrapping paper for a school fundraiser. Customers can buy rolls of plain wrapping paper and rolls of shiny wrapping paper. Abhasra sold 10 rolls of plain wrapping paper and 4 rolls of shiny wrapping paper for a total of $170. Aliyah sold 5 rolls of plain wrapping paper and 3 rolls of shiny wrapping paper for a total of $105. Find the cost each of one roll of plain wrapping paper and one roll of shiny wrapping paper.

Answer 1

• $9 and $20

Explanation:

• Plain wrapping paper - p
• Shiny wrapping paper - s

Equations:

• 10p + 4s = 170
• 5p + 3s = 105

Double the second equation and subtract from the first one:

• 10p + 4s - 10p - 6s = 170 - 210
• -2s = - 40
• s = 20

Find p:

• 10p + 4*20 = 170
• 10p = 90
• p = 9