Adam pays $40 for 4 stickers and 2 marbles.
2 stickers cost as much as 1 marble.
- How much is 1 sticker?
- How much is 1 marble?
- How much is 3 marbles and 2 stickers?
(a)
Choose the smaller group to be 1 u.
Cost of 1 sticker = 1 u
Cost of 2 stickers = 2 u
Cost of 1 marble = 2 u
Cost of 4 stickers
= 4 x 1 u
= 4 u
Cost of 2 marbles
= 2 x 2 u
= 4 u
Total cost of 4 stickers and 2 marbles
= 4 u + 4 u
= 8 u
8 u = 40
1 u = 40 ÷ 8 = 5
Cost of 1 sticker
= 1 u
= $5
(b)
Cost of 1 marble
= 2 u
= 2 x 5
= $10
(c)
Cost of 3 marbles and 2 stickers
= 3 x 2 u + 2 x 1 u
= 6 u + 2 u
= 8 u
= 8 x 5
= $40
Answer(s): (a) $5; (b) $10; (c) $40