Adam spends $13.20 on 5 beads and 6 marbles.
A bead costs $1.10 more than 1 marble.
- How much does 1 bead cost?
- How much do 6 beads cost?
- How much do a marble and 6 beads cost?
- How much do 6 beads cost more than 1 marble?
(a)
Let the cheaper item be 1 u.
Cost of 1 marble = 1 u
Cost of 1 bead = 1 u + 1.10
Total cost of 5 beads and 6 marbles
= 5(1 u + 1.10) + 6 u
= 5 u + 5.50 + 6 u
= 5 u + 6 u + 5.50
= 11 u + 5.50
11 u + 5.50 = 13.20
11 u = 13.20 - 5.50
11 u = 7.70
1 u = 7.70 ÷ 11 = 0.70
Cost of 1 bead
= 1 u + 1.10
= 0.70 + 1.10
= $1.80
(b)
Cost of 6 beads
= 6 x 1.80
= $10.80
(c)
Cost of 1 marble and 6 beads
= 0.70 + 10.80
= $11.50
(d)
Cost of 6 beads more than 1 marble
= 10.80 - 0.70
= $10.10
Answer(s): (a) $1.80; (b) $10.80; (c) $11.50; (d) $10.10