If Adam buys 3 stickers and 4 beads, it costs $41.70.
If Adam buys 4 stickers and 3 beads, he will need another $4.10.
- Find the cost of 1 sticker and 1 bead.
- Find the cost of 1 sticker.
- Find the cost of 1 bead.
(a)
3 stickers + 4 beads = 41.70 --- (1)
4 stickers + 3 beads = 41.70 + 4.10 = 45.80 --- (2)
(1) + (2)
7 stickers + 7 beads = 87.50 --- (3)
(3)
÷ 7 1 sticker + 1 bead = 87.50 ÷ 7 = 12.50 --- (4)
Cost of 1 sticker and 1 bead = $12.50
(b)
4 stickers + 3 beads = 45.80 --- (2)
(4)
x 3 3 stickers + 3 beads = 3 x 12.50 = 37.50 --- (5)
(2) - (5)
4 stickers + 3 beads - 3 stickers - 3 beads = 45.80 - 37.50
4 stickers - 3 stickers + 3 beads - 3 beads = 8.30
1 sticker = 8.30
Cost of 1 sticker = $8.30
(c)
Substitute 1 sticker = 8.30 into (4).
1 sticker + 1 bead = 12.50
8.30 + 1 bead = 12.50
1 bead = 12.50 - 8.30 = 4.20
Cost of 1 bead = $4.20
Answer(s): (a) $12.50; (b) $8.30; (c) $4.20