Adam spends $12.90 on 3 beads and 4 stickers.
A bead costs $1.50 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 + 1.50
Total cost of 3 beads and 4 stickers
= 3(1 u + 1.50) + 4 u
= 3 u + 4.50 + 4 u
= 3 u + 4 u + 4.50
= 7 u + 4.50
7 u + 4.50 = 12.90
7 u = 12.90 - 4.50
7 u = 8.40
1 u = 8.40 ÷ 7 = 1.20
Cost of 1 bead
= 1 u + 1.50
= 1.20 + 1.50
= $2.70
(b)
Cost of 7 beads
= 7 x 2.70
= $18.90
(c)
Cost of 1 sticker and 7 beads
= 1.20 + 18.90
= $20.10
(d)
Cost of 7 beads more than 1 sticker
= 18.90 - 1.20
= $17.70
Answer(s): (a) $2.70; (b) $18.90; (c) $20.10; (d) $17.70