Adam pays $25.60 for 1 marble and 8 stickers.
The marble costs $2.20 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 8 marbles and 2 stickers?
(a)
Choose the cheaper item to be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 marble = 1 u + 2.20
Cost of 8 stickers
= 8 x 1 u
= 8 u
Total cost of 1 marble and 8 stickers
= 1 u + 2.20 + 8 u
= 9 u + 2.20
9 u + 2.20 = 25.60
9 u = 25.60 - 2.20
9 u = 23.40
1 u = 23.40 ÷ 9 = 2.60
Cost of 1 marble
= 2.60 + 2.20
= $4.80
(b)
Cost of 8 marbles and 2 stickers
= 8 x 4.80 + 2 x 2.60
= 38.40 + 5.20
= $43.60
Answer(s): (a) $4.80; (b) $43.60