Adam spends $15.70 on 5 beads and 6 marbles.
A bead costs $2.70 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 + 2.70
Total cost of 5 beads and 6 marbles
= 5(1 u + 2.70) + 6 u
= 5 u + 13.50 + 6 u
= 5 u + 6 u + 13.50
= 11 u + 13.50
11 u + 13.50 = 15.70
11 u = 15.70 - 13.50
11 u = 2.20
1 u = 2.20 ÷ 11 = 0.20
Cost of 1 bead
= 1 u + 2.70
= 0.20 + 2.70
= $2.90
(b)
Cost of 6 beads
= 6 x 2.90
= $17.40
(c)
Cost of 1 marble and 6 beads
= 0.20 + 17.40
= $17.60
(d)
Cost of 6 beads more than 1 marble
= 17.40 - 0.20
= $17.20
Answer(s): (a) $2.90; (b) $17.40; (c) $17.60; (d) $17.20