2 stickers and 1 bead cost $11.40.
1 sticker and 2 beads cost $9.90.
- 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 = 11.40 --- (1)
1 sticker + 2 beads = 9.90 --- (2)
(1) + (2)
3 stickers + 3 beads = 11.40 + 9.90
3 stickers + 3 beads = 21.30 --- (3)
(3)
÷ 3
3 stickers + 3 beads = 21.30
1 sticker + 1 bead = 21.30 ÷ 3
1 sticker + 1 bead = 7.10 --- (4)
Cost of 1 sticker and 1 bead = $7.10
(b)
(2) - (4)
(1 sticker + 2 beads) - (1 sticker + 1 marble) = 9.90 - 7.10
1 sticker - 1 sticker + 2 beads - 1 bead = 2.80
1 bead = 2.80
Cost of 1 bead = $2.80
(c)
Substitute 1 bead = 2.80 into (4).
1 sticker + 1 bead = 7.10
1 sticker + 2.80 = 7.10
1 sticker = 7.10 - 2.80 = 4.30
Cost of 1 sticker = $4.30
(d)
(4)
x 8 1 sticker + 1 bead = 7.10
8 x (1 sticker + 1 marble) = 8 x 7.10
8 stickers + 8 beads = 56.80
Cost of 8 stickers and 8 beads = $56.80
Answer(s): (a) $7.10; (b) $2.80; (c) $4.30; (d) $56.80