If Adam buys 4 stickers and 5 beads, it costs $40.40.
If Adam buys 5 stickers and 4 beads, he will need another $2.90.
- Find the cost of 1 sticker and 1 bead.
- Find the cost of 1 sticker.
- Find the cost of 1 bead.
(a)
4 stickers + 5 beads = 40.40 --- (1)
5 stickers + 4 beads = 40.40 + 2.90 = 43.30 --- (2)
(1) + (2)
9 stickers + 9 beads = 83.70 --- (3)
(3)
÷ 9 1 sticker + 1 bead = 83.70 ÷ 9 = 9.30 --- (4)
Cost of 1 sticker and 1 bead = $9.30
(b)
5 stickers + 4 beads = 43.30 --- (2)
(4)
x 4 4 stickers + 4 beads = 4 x 9.30 = 37.20 --- (5)
(2) - (5)
5 stickers + 4 beads - 4 stickers - 4 beads = 43.30 - 37.20
5 stickers - 4 stickers + 4 beads - 4 beads = 6.10
1 sticker = 6.10
Cost of 1 sticker = $6.10
(c)
Substitute 1 sticker = 6.10 into (4).
1 sticker + 1 bead = 9.30
6.10 + 1 bead = 9.30
1 bead = 9.30 - 6.10 = 3.20
Cost of 1 bead = $3.20
Answer(s): (a) $9.30; (b) $6.10; (c) $3.20