Adam spends $16.10 on 2 stickers and 3 marbles.
A sticker costs $2.30 more than 1 marble.
- How much does 1 sticker cost?
- How much do 8 stickers cost?
- How much do a marble and 8 stickers cost?
- How much do 8 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 = 16.10
5 u = 16.10 - 4.60
5 u = 11.50
1 u = 11.50 ÷ 5 = 2.30
Cost of 1 sticker
= 1 u + 2.30
= 2.30 + 2.30
= $4.60
(b)
Cost of 8 stickers
= 8 x 4.60
= $36.80
(c)
Cost of 1 marble and 8 stickers
= 2.30 + 36.80
= $39.10
(d)
Cost of 8 stickers more than 1 marble
= 36.80 - 2.30
= $34.50
Answer(s): (a) $4.60; (b) $36.80; (c) $39.10; (d) $34.50