If Adam buys 2 beads and 3 marbles, it costs $33.80.
If Adam buys 3 beads and 2 marbles, he will have $2.10 left.
- Find the cost of 1 bead and 1 marble.
- Find the cost of 1 bead.
- Find the cost of 1 marble.
(a)
2 beads + 3 marbles = 33.80 --- (1)
3 beads + 2 marbles = 33.80 - 2.10 = 31.70 --- (2)
(1) + (2)
5 beads + 5 marbles = 65.50 --- (3)
(3)
÷ 5 1 bead + 1 marble = 65.50 ÷ 5 = 13.10 --- (4)
Cost of 1 bead and 1 marble = $13.10
(b)
(4)
x 2 2 beads + 2 marbles = 2 x 13.10 = 26.20 --- (5)
(2) - (5)
3 beads + 2 marbles - 2 beads - 2 marbles = 31.70 - 26.20
3 beads - 2 beads - 2 marbles + 2 marbles = 5.50
1 bead = 5.50
Cost of 1 bead = $5.50
(c)
Substitute 1 bead = 5.50 into (4).
1 bead + 1 marble = 13.10
5.50 + 1 marble = 13.10
1 marble = 13.10 - 5.50 = 7.60
Cost of 1 marble = $7.60
Answer(s): (a) $13.10; (b) $5.50; (c) $7.60