2 stickers and 1 bead cost $9.90.
1 sticker and 2 beads cost $8.40.
- 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 4 stickers and 4 beads.
(a)
2 stickers + 1 bead = 9.90 --- (1)
1 sticker + 2 beads = 8.40 --- (2)
(1) + (2)
3 stickers + 3 beads = 9.90 + 8.40
3 stickers + 3 beads = 18.30 --- (3)
(3)
÷ 3
3 stickers + 3 beads = 18.30
1 sticker + 1 bead = 18.30 ÷ 3
1 sticker + 1 bead = 6.10 --- (4)
Cost of 1 sticker and 1 bead = $6.10
(b)
(2) - (4)
(1 sticker + 2 beads) - (1 sticker + 1 marble) = 8.40 - 6.10
1 sticker - 1 sticker + 2 beads - 1 bead = 2.30
1 bead = 2.30
Cost of 1 bead = $2.30
(c)
Substitute 1 bead = 2.30 into (4).
1 sticker + 1 bead = 6.10
1 sticker + 2.30 = 6.10
1 sticker = 6.10 - 2.30 = 3.80
Cost of 1 sticker = $3.80
(d)
(4)
x 4 1 sticker + 1 bead = 6.10
4 x (1 sticker + 1 marble) = 4 x 6.10
4 stickers + 4 beads = 24.40
Cost of 4 stickers and 4 beads = $24.40
Answer(s): (a) $6.10; (b) $2.30; (c) $3.80; (d) $24.40