Adam spends $13.10 on 2 beads and 3 marbles.
A bead costs $2.80 more than 1 marble.
- How much does 1 bead cost?
- How much do 8 beads cost?
- How much do a marble and 8 beads cost?
- How much do 8 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 + 2.80
Total cost of 2 beads and 3 marbles
= 2(1 u + 2.80) + 3 u
= 2 u + 5.60 + 3 u
= 2 u + 3 u + 5.60
= 5 u + 5.60
5 u + 5.60 = 13.10
5 u = 13.10 - 5.60
5 u = 7.50
1 u = 7.50 ÷ 5 = 1.50
Cost of 1 bead
= 1 u + 2.80
= 1.50 + 2.80
= $4.30
(b)
Cost of 8 beads
= 8 x 4.30
= $34.40
(c)
Cost of 1 marble and 8 beads
= 1.50 + 34.40
= $35.90
(d)
Cost of 8 beads more than 1 marble
= 34.40 - 1.50
= $32.90
Answer(s): (a) $4.30; (b) $34.40; (c) $35.90; (d) $32.90