If Adam buys 4 beads and 5 stickers, it costs $54.90.
If Adam buys 5 beads and 4 stickers, he will need another $0.90.
- Find the cost of 1 bead and 1 sticker.
- Find the cost of 1 bead.
- Find the cost of 1 sticker.
(a)
4 beads + 5 stickers = 54.90 --- (1)
5 beads + 4 stickers = 54.90 + 0.90 = 55.80 --- (2)
(1) + (2)
9 beads + 9 stickers = 110.70 --- (3)
(3)
÷ 9 1 bead + 1 sticker = 110.70 ÷ 9 = 12.30 --- (4)
Cost of 1 bead and 1 sticker = $12.30
(b)
5 beads + 4 stickers = 55.80 --- (2)
(4)
x 4 4 beads + 4 stickers = 4 x 12.30 = 49.20 --- (5)
(2) - (5)
5 beads + 4 stickers - 4 beads - 4 stickers = 55.80 - 49.20
5 beads - 4 beads + 4 stickers - 4 stickers = 6.60
1 bead = 6.60
Cost of 1 bead = $6.60
(c)
Substitute 1 bead = 6.60 into (4).
1 bead + 1 sticker = 12.30
6.60 + 1 sticker = 12.30
1 sticker = 12.30 - 6.60 = 5.70
Cost of 1 sticker = $5.70
Answer(s): (a) $12.30; (b) $6.60; (c) $5.70