If Adam buys 5 beads and 6 marbles, it costs $57.70.
If Adam buys 6 beads and 5 marbles, he will have $4.30 left.
- Find the cost of 1 bead and 1 marble.
- Find the cost of 1 bead.
- Find the cost of 1 marble.
(a)
5 beads + 6 marbles = 57.70 --- (1)
6 beads + 5 marbles = 57.70 - 4.30 = 53.40 --- (2)
(1) + (2)
11 beads + 11 marbles = 111.10 --- (3)
(3)
÷ 11 1 bead + 1 marble = 111.10 ÷ 11 = 10.10 --- (4)
Cost of 1 bead and 1 marble = $10.10
(b)
(4)
x 5 5 beads + 5 marbles = 5 x 10.10 = 50.50 --- (5)
(2) - (5)
6 beads + 5 marbles - 5 beads - 5 marbles = 53.40 - 50.50
6 beads - 5 beads - 5 marbles + 5 marbles = 2.90
1 bead = 2.90
Cost of 1 bead = $2.90
(c)
Substitute 1 bead = 2.90 into (4).
1 bead + 1 marble = 10.10
2.90 + 1 marble = 10.10
1 marble = 10.10 - 2.90 = 7.20
Cost of 1 marble = $7.20
Answer(s): (a) $10.10; (b) $2.90; (c) $7.20