Adam pays $38.80 for 1 marble and 5 stickers.
The marble costs $2.20 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 5 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 5 stickers
= 5 x 1 u
= 5 u
Total cost of 1 marble and 5 stickers
= 1 u + 2.20 + 5 u
= 6 u + 2.20
6 u + 2.20 = 38.80
6 u = 38.80 - 2.20
6 u = 36.60
1 u = 36.60 ÷ 6 = 6.10
Cost of 1 marble
= 6.10 + 2.20
= $8.30
(b)
Cost of 5 marbles and 2 stickers
= 5 x 8.30 + 2 x 6.10
= 41.50 + 12.20
= $53.70
Answer(s): (a) $8.30; (b) $53.70