If Adam buys 3 stickers and 4 beads, it costs $41.10.
If Adam buys 4 stickers and 3 beads, he will need another $0.40.
- 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 = 41.10 --- (1)
4 stickers + 3 beads = 41.10 + 0.40 = 41.50 --- (2)
(1) + (2)
7 stickers + 7 beads = 82.60 --- (3)
(3)
÷ 7 1 sticker + 1 bead = 82.60 ÷ 7 = 11.80 --- (4)
Cost of 1 sticker and 1 bead = $11.80
(b)
4 stickers + 3 beads = 41.50 --- (2)
(4)
x 3 3 stickers + 3 beads = 3 x 11.80 = 35.40 --- (5)
(2) - (5)
4 stickers + 3 beads - 3 stickers - 3 beads = 41.50 - 35.40
4 stickers - 3 stickers + 3 beads - 3 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 = 11.80
6.10 + 1 bead = 11.80
1 bead = 11.80 - 6.10 = 5.70
Cost of 1 bead = $5.70
Answer(s): (a) $11.80; (b) $6.10; (c) $5.70