Adam spends $16.50 on 3 stickers and 4 beads.
A sticker costs $2.70 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 + 2.70
Total cost of 3 stickers and 4 beads
= 3(1 u + 2.70) + 4 u
= 3 u + 8.10 + 4 u
= 3 u + 4 u + 8.10
= 7 u + 8.10
7 u + 8.10 = 16.50
7 u = 16.50 - 8.10
7 u = 8.40
1 u = 8.40 ÷ 7 = 1.20
Cost of 1 sticker
= 1 u + 2.70
= 1.20 + 2.70
= $3.90
(b)
Cost of 7 stickers
= 7 x 3.90
= $27.30
(c)
Cost of 1 bead and 7 stickers
= 1.20 + 27.30
= $28.50
(d)
Cost of 7 stickers more than 1 bead
= 27.30 - 1.20
= $26.10
Answer(s): (a) $3.90; (b) $27.30; (c) $28.50; (d) $26.10