Adam pays $4.20 for a marble and a bead.
The marble costs 5 times as much as the bead.
- What is the cost of 1 marble?
- How much is the cost of 4 beads and 5 marbles?
(a)
Cost of a bead = 1 u
Cost of a marble = 5 u
Total cost of a bead and a marble
= 1 u + 5 u
= 6 u
6 u = 4.20
1 u = 4.20 ÷ 6 = 0.70
Cost of the marble
= 5 u
= 5 x 0.70
= $3.50
(b)
Cost of 4 beads and 5 marbles
= 4 x 1 u + 5 x 5 u
= 4 u + 25 u
= 29 u
= 29 x 0.70
= $20.30
Answer(s): (a) $3.50; (b) $20.30