Adam pays $43.20 for 1 marble and 4 stickers.
The marble costs $2.70 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 4 marbles and 6 stickers?
(a)
Choose the cheaper item to be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 marble = 1 u + 2.70
Cost of 4 stickers
= 4 x 1 u
= 4 u
Total cost of 1 marble and 4 stickers
= 1 u + 2.70 + 4 u
= 5 u + 2.70
5 u + 2.70 = 43.20
5 u = 43.20 - 2.70
5 u = 40.50
1 u = 40.50 ÷ 5 = 8.10
Cost of 1 marble
= 8.10 + 2.70
= $10.80
(b)
Cost of 4 marbles and 6 stickers
= 4 x 10.80 + 6 x 8.10
= 43.20 + 48.60
= $91.80
Answer(s): (a) $10.80; (b) $91.80