Adam spends $12.70 on 3 beads and 4 stickers.
A bead costs $1.20 more than 1 sticker.
- How much does 1 bead cost?
- How much do 7 beads cost?
- How much do a sticker and 7 beads cost?
- How much do 7 beads cost more than 1 sticker?
(a)
Let the cheaper item be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 bead = 1 u + 1.20
Total cost of 3 beads and 4 stickers
= 3(1 u + 1.20) + 4 u
= 3 u + 3.60 + 4 u
= 3 u + 4 u + 3.60
= 7 u + 3.60
7 u + 3.60 = 12.70
7 u = 12.70 - 3.60
7 u = 9.10
1 u = 9.10 ÷ 7 = 1.30
Cost of 1 bead
= 1 u + 1.20
= 1.30 + 1.20
= $2.50
(b)
Cost of 7 beads
= 7 x 2.50
= $17.50
(c)
Cost of 1 sticker and 7 beads
= 1.30 + 17.50
= $18.80
(d)
Cost of 7 beads more than 1 sticker
= 17.50 - 1.30
= $16.20
Answer(s): (a) $2.50; (b) $17.50; (c) $18.80; (d) $16.20