2 beads and 1 sticker cost $10.10.
1 bead and 2 stickers cost $11.50.
- Find the cost of 1 bead and 1 sticker.
- Find the cost of 1 sticker.
- Find the cost of 1 bead.
- Find the cost of 7 beads and 7 stickers.
(a)
2 beads + 1 sticker = 10.10 --- (1)
1 bead + 2 stickers = 11.50 --- (2)
(1) + (2)
3 beads + 3 stickers = 10.10 + 11.50
3 beads + 3 stickers = 21.60 --- (3)
(3)
÷ 3
3 beads + 3 stickers = 21.60
1 bead + 1 sticker = 21.60 ÷ 3
1 bead + 1 sticker = 7.20 --- (4)
Cost of 1 bead and 1 sticker = $7.20
(b)
(2) - (4)
(1 bead + 2 stickers) - (1 bead + 1 marble) = 11.50 - 7.20
1 bead - 1 bead + 2 stickers - 1 sticker = 4.30
1 sticker = 4.30
Cost of 1 sticker = $4.30
(c)
Substitute 1 sticker = 4.30 into (4).
1 bead + 1 sticker = 7.20
1 bead + 4.30 = 7.20
1 bead = 7.20 - 4.30 = 2.90
Cost of 1 bead = $2.90
(d)
(4)
x 7 1 bead + 1 sticker = 7.20
7 x (1 bead + 1 marble) = 7 x 7.20
7 beads + 7 stickers = 50.40
Cost of 7 beads and 7 stickers = $50.40
Answer(s): (a) $7.20; (b) $4.30; (c) $2.90; (d) $50.40