Adam pays $32.90 for 1 marble and 4 stickers.
The marble costs $1.40 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 + 1.40
Cost of 4 stickers
= 4 x 1 u
= 4 u
Total cost of 1 marble and 4 stickers
= 1 u + 1.40 + 4 u
= 5 u + 1.40
5 u + 1.40 = 32.90
5 u = 32.90 - 1.40
5 u = 31.50
1 u = 31.50 ÷ 5 = 6.30
Cost of 1 marble
= 6.30 + 1.40
= $7.70
(b)
Cost of 4 marbles and 6 stickers
= 4 x 7.70 + 6 x 6.30
= 30.80 + 37.80
= $68.60
Answer(s): (a) $7.70; (b) $68.60