Adam pays $33.40 for 1 marble and 5 stickers.
The marble costs $2.80 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 + 2.80
Cost of 5 stickers
= 5 x 1 u
= 5 u
Total cost of 1 marble and 5 stickers
= 1 u + 2.80 + 5 u
= 6 u + 2.80
6 u + 2.80 = 33.40
6 u = 33.40 - 2.80
6 u = 30.60
1 u = 30.60 ÷ 6 = 5.10
Cost of 1 marble
= 5.10 + 2.80
= $7.90
(b)
Cost of 5 marbles and 2 stickers
= 5 x 7.90 + 2 x 5.10
= 39.50 + 10.20
= $49.70
Answer(s): (a) $7.90; (b) $49.70