2 stickers and 1 bead cost $10.10.
1 sticker and 2 beads cost $11.50.
- Find the cost of 1 sticker and 1 bead.
- Find the cost of 1 bead.
- Find the cost of 1 sticker.
- Find the cost of 8 stickers and 8 beads.
(a)
2 stickers + 1 bead = 10.10 --- (1)
1 sticker + 2 beads = 11.50 --- (2)
(1) + (2)
3 stickers + 3 beads = 10.10 + 11.50
3 stickers + 3 beads = 21.60 --- (3)
(3)
÷ 3
3 stickers + 3 beads = 21.60
1 sticker + 1 bead = 21.60 ÷ 3
1 sticker + 1 bead = 7.20 --- (4)
Cost of 1 sticker and 1 bead = $7.20
(b)
(2) - (4)
(1 sticker + 2 beads) - (1 sticker + 1 marble) = 11.50 - 7.20
1 sticker - 1 sticker + 2 beads - 1 bead = 4.30
1 bead = 4.30
Cost of 1 bead = $4.30
(c)
Substitute 1 bead = 4.30 into (4).
1 sticker + 1 bead = 7.20
1 sticker + 4.30 = 7.20
1 sticker = 7.20 - 4.30 = 2.90
Cost of 1 sticker = $2.90
(d)
(4)
x 8 1 sticker + 1 bead = 7.20
8 x (1 sticker + 1 marble) = 8 x 7.20
8 stickers + 8 beads = 57.60
Cost of 8 stickers and 8 beads = $57.60
Answer(s): (a) $7.20; (b) $4.30; (c) $2.90; (d) $57.60