4 beads and 1 sticker cost $16.70.
1 bead and 4 stickers cost $9.80.
- 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 4 beads and 4 stickers.
(a)
4 beads + 1 sticker = 16.70 --- (1)
1 bead + 4 stickers = 9.80 --- (2)
(1) + (2)
5 beads + 5 stickers = 16.70 + 9.80
5 beads + 5 stickers = 26.50 --- (3)
(3)
÷ 55 beads + 5 stickers = 26.50
1 bead + 1 sticker = 26.50 ÷ 5
1 bead + 1 sticker = 5.30 --- (4)
(b)
(2) - (4)
(1 bead + 4 stickers) - (1 bead + 1 marble) = 9.80 - 5.30
1 bead - 1 bead + 4 stickers - 1 sticker = 4.50
3 stickers = 4.50
1 sticker = 4.50 ÷ 3 = 1.50
Cost of 1 sticker = $1.50
(c)
Substitute 1 sticker = 1.50 into (4).
1 bead + 1 sticker = 5.30
1 bead + 1.50 = 5.30
1 bead = 5.30 - 1.50 = 3.80
Cost of 1 bead = $3.80
(d)
(4)
x 4 1 bead + 1 sticker = 5.30
4 x (1 bead + 1 marble) = 4 x 5.30
4 beads + 4 stickers = 21.20
Cost of 4 beads and 4 stickers = $21.20
Answer(s): (a) $5.30; (b) $1.50; (c) $3.80; (d) $21.20