2 beads and 1 sticker cost $10.10.
1 bead and 2 stickers cost $8.50.
- 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 = 8.50 --- (2)
(1) + (2)
3 beads + 3 stickers = 10.10 + 8.50
3 beads + 3 stickers = 18.60 --- (3)
(3)
÷ 3
3 beads + 3 stickers = 18.60
1 bead + 1 sticker = 18.60 ÷ 3
1 bead + 1 sticker = 6.20 --- (4)
Cost of 1 bead and 1 sticker = $6.20
(b)
(2) - (4)
(1 bead + 2 stickers) - (1 bead + 1 marble) = 8.50 - 6.20
1 bead - 1 bead + 2 stickers - 1 sticker = 2.30
1 sticker = 2.30
Cost of 1 sticker = $2.30
(c)
Substitute 1 sticker = 2.30 into (4).
1 bead + 1 sticker = 6.20
1 bead + 2.30 = 6.20
1 bead = 6.20 - 2.30 = 3.90
Cost of 1 bead = $3.90
(d)
(4)
x 7 1 bead + 1 sticker = 6.20
7 x (1 bead + 1 marble) = 7 x 6.20
7 beads + 7 stickers = 43.40
Cost of 7 beads and 7 stickers = $43.40
Answer(s): (a) $6.20; (b) $2.30; (c) $3.90; (d) $43.40