Adam pays $18.40 for 1 marble and 5 stickers.
The marble costs $1.60 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 5 marbles and 4 stickers?
(a)
Choose the cheaper item to be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 marble = 1 u + 1.60
Cost of 5 stickers
= 5 x 1 u
= 5 u
Total cost of 1 marble and 5 stickers
= 1 u + 1.60 + 5 u
= 6 u + 1.60
6 u + 1.60 = 18.40
6 u = 18.40 - 1.60
6 u = 16.80
1 u = 16.80 ÷ 6 = 2.80
Cost of 1 marble
= 2.80 + 1.60
= $4.40
(b)
Cost of 5 marbles and 4 stickers
= 5 x 4.40 + 4 x 2.80
= 22.00 + 11.20
= $33.20
Answer(s): (a) $4.40; (b) $33.20