Adam spends $14.60 on 4 marbles and 5 stickers.
A marble costs $2.30 more than 1 sticker.
- How much does 1 marble cost?
- How much do 5 marbles cost?
- How much do a sticker and 5 marbles cost?
- How much do 5 marbles cost more than 1 sticker?
(a)
Let the cheaper item be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 marble = 1 u + 2.30
Total cost of 4 marbles and 5 stickers
= 4(1 u + 2.30) + 5 u
= 4 u + 9.20 + 5 u
= 4 u + 5 u + 9.20
= 9 u + 9.20
9 u + 9.20 = 14.60
9 u = 14.60 - 9.20
9 u = 5.40
1 u = 5.40 ÷ 9 = 0.60
Cost of 1 marble
= 1 u + 2.30
= 0.60 + 2.30
= $2.90
(b)
Cost of 5 marbles
= 5 x 2.90
= $14.50
(c)
Cost of 1 sticker and 5 marbles
= 0.60 + 14.50
= $15.10
(d)
Cost of 5 marbles more than 1 sticker
= 14.50 - 0.60
= $13.90
Answer(s): (a) $2.90; (b) $14.50; (c) $15.10; (d) $13.90