Adam spends $12.10 on 2 stickers and 3 marbles.
A sticker costs $2.30 more than 1 marble.
- How much does 1 sticker cost?
- How much do 6 stickers cost?
- How much do a marble and 6 stickers cost?
- How much do 6 stickers cost more than 1 marble?
(a)
Let the cheaper item be 1 u.
Cost of 1 marble = 1 u
Cost of 1 sticker = 1 u + 2.30
Total cost of 2 stickers and 3 marbles
= 2(1 u + 2.30) + 3 u
= 2 u + 4.60 + 3 u
= 2 u + 3 u + 4.60
= 5 u + 4.60
5 u + 4.60 = 12.10
5 u = 12.10 - 4.60
5 u = 7.50
1 u = 7.50 ÷ 5 = 1.50
Cost of 1 sticker
= 1 u + 2.30
= 1.50 + 2.30
= $3.80
(b)
Cost of 6 stickers
= 6 x 3.80
= $22.80
(c)
Cost of 1 marble and 6 stickers
= 1.50 + 22.80
= $24.30
(d)
Cost of 6 stickers more than 1 marble
= 22.80 - 1.50
= $21.30
Answer(s): (a) $3.80; (b) $22.80; (c) $24.30; (d) $21.30