Adam pays $49 for 3 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 4 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 3 stickers
= 3 x 1 u
= 3 u
Cost of 2 marbles
= 2 x 2 u
= 4 u
Total cost of 3 stickers and 2 marbles
= 3 u + 4 u
= 7 u
7 u = 49
1 u = 49 ÷ 7 = 7
Cost of 1 sticker
= 1 u
= $7
(b)
Cost of 1 marble
= 2 u
= 2 x 7
= $14
(c)
Cost of 4 marbles and 2 stickers
= 4 x 2 u + 2 x 1 u
= 8 u + 2 u
= 10 u
= 10 x 7
= $70
Answer(s): (a) $7; (b) $14; (c) $70