If Adam buys 2 beads and 3 marbles, it costs $26.40.
If Adam buys 3 beads and 2 marbles, he will have $5.30 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 = 26.40 --- (1)
3 beads + 2 marbles = 26.40 - 5.30 = 21.10 --- (2)
(1) + (2)
5 beads + 5 marbles = 47.50 --- (3)
(3)
÷ 5 1 bead + 1 marble = 47.50 ÷ 5 = 9.50 --- (4)
Cost of 1 bead and 1 marble = $9.50
(b)
(4)
x 2 2 beads + 2 marbles = 2 x 9.50 = 190 --- (5)
(2) - (5)
3 beads + 2 marbles - 2 beads - 2 marbles = 21.10 - 190
3 beads - 2 beads - 2 marbles + 2 marbles = 2.10
1 bead = 2.10
Cost of 1 bead = $2.10
(c)
Substitute 1 bead = 2.10 into (4).
1 bead + 1 marble = 9.50
2.10 + 1 marble = 9.50
1 marble = 9.50 - 2.10 = 7.40
Cost of 1 marble = $7.40
Answer(s): (a) $9.50; (b) $2.10; (c) $7.40