Adam spends $12.10 on 4 stickers and 5 beads.
A sticker costs $1.90 more than 1 bead.
- How much does 1 sticker cost?
- How much do 7 stickers cost?
- How much do a bead and 7 stickers cost?
- How much do 7 stickers cost more than 1 bead?
(a)
Let the cheaper item be 1 u.
Cost of 1 bead = 1 u
Cost of 1 sticker = 1 u + 1.90
Total cost of 4 stickers and 5 beads
= 4(1 u + 1.90) + 5 u
= 4 u + 7.60 + 5 u
= 4 u + 5 u + 7.60
= 9 u + 7.60
9 u + 7.60 = 12.10
9 u = 12.10 - 7.60
9 u = 4.50
1 u = 4.50 ÷ 9 = 0.50
Cost of 1 sticker
= 1 u + 1.90
= 0.50 + 1.90
= $2.40
(b)
Cost of 7 stickers
= 7 x 2.40
= $16.80
(c)
Cost of 1 bead and 7 stickers
= 0.50 + 16.80
= $17.30
(d)
Cost of 7 stickers more than 1 bead
= 16.80 - 0.50
= $16.30
Answer(s): (a) $2.40; (b) $16.80; (c) $17.30; (d) $16.30