Adam pays $22 for 2 marbles and 3 beads.
3 marbles cost as much as 1 bead.
- How much is 1 marble?
- How much is 1 bead?
- How much is 2 beads and 3 marbles?
(a)
Choose the smaller group to be 1 u.
Cost of 1 marble = 1 u
Cost of 3 marbles = 3 u
Cost of 1 bead = 3 u
Cost of 2 marbles
= 2 x 1 u
= 2 u
Cost of 3 beads
= 3 x 3 u
= 9 u
Total cost of 2 marbles and 3 beads
= 2 u + 9 u
= 11 u
11 u = 22
1 u = 22 ÷ 11 = 2
Cost of 1 marble
= 1 u
= $2
(b)
Cost of 1 bead
= 3 u
= 3 x 2
= $6
(c)
Cost of 2 beads and 3 marbles
= 2 x 3 u + 3 x 1 u
= 6 u + 3 u
= 9 u
= 9 x 2
= $18
Answer(s): (a) $2; (b) $6; (c) $18