Adam pays $32.90 for 1 marble and 4 stickers.
The marble costs $2.40 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 4 marbles and 3 stickers?
(a)
Choose the cheaper item to be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 marble = 1 u + 2.40
Cost of 4 stickers
= 4 x 1 u
= 4 u
Total cost of 1 marble and 4 stickers
= 1 u + 2.40 + 4 u
= 5 u + 2.40
5 u + 2.40 = 32.90
5 u = 32.90 - 2.40
5 u = 30.50
1 u = 30.50 ÷ 5 = 6.10
Cost of 1 marble
= 6.10 + 2.40
= $8.50
(b)
Cost of 4 marbles and 3 stickers
= 4 x 8.50 + 3 x 6.10
= 34.00 + 18.30
= $52.30
Answer(s): (a) $8.50; (b) $52.30