If Adam buys 4 stickers and 5 beads, it costs $49.90.
If Adam buys 5 stickers and 4 beads, he will need another $3.70.
- 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 = 49.90 --- (1)
5 stickers + 4 beads = 49.90 + 3.70 = 53.60 --- (2)
(1) + (2)
9 stickers + 9 beads = 103.50 --- (3)
(3)
÷ 9 1 sticker + 1 bead = 103.50 ÷ 9 = 11.50 --- (4)
Cost of 1 sticker and 1 bead = $11.50
(b)
5 stickers + 4 beads = 53.60 --- (2)
(4)
x 4 4 stickers + 4 beads = 4 x 11.50 = 460 --- (5)
(2) - (5)
5 stickers + 4 beads - 4 stickers - 4 beads = 53.60 - 460
5 stickers - 4 stickers + 4 beads - 4 beads = 7.60
1 sticker = 7.60
Cost of 1 sticker = $7.60
(c)
Substitute 1 sticker = 7.60 into (4).
1 sticker + 1 bead = 11.50
7.60 + 1 bead = 11.50
1 bead = 11.50 - 7.60 = 3.90
Cost of 1 bead = $3.90
Answer(s): (a) $11.50; (b) $7.60; (c) $3.90