Adam pays $36.20 for 1 marble and 5 stickers.
The marble costs $2.60 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 5 marbles and 7 stickers?
(a)
Choose the cheaper item to be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 marble = 1 u + 2.60
Cost of 5 stickers
= 5 x 1 u
= 5 u
Total cost of 1 marble and 5 stickers
= 1 u + 2.60 + 5 u
= 6 u + 2.60
6 u + 2.60 = 36.20
6 u = 36.20 - 2.60
6 u = 33.60
1 u = 33.60 ÷ 6 = 5.60
Cost of 1 marble
= 5.60 + 2.60
= $8.20
(b)
Cost of 5 marbles and 7 stickers
= 5 x 8.20 + 7 x 5.60
= 41.00 + 39.20
= $80.20
Answer(s): (a) $8.20; (b) $80.20