Adam pays $11 for 2 stickers and 3 marbles.
6 stickers cost as much as 2 marbles.
- How much is 1 sticker?
- How much is 1 marble?
- How much is 4 marbles and 3 stickers?
(a)
Choose the smaller group to be 1 u.
Cost of 6 stickers = Cost of 2 marbles
Cost of 3 stickers = Cost of 1 marble
Cost of 1 sticker = 1 u
Cost of 1 marble = 3 u
Cost of 2 stickers
= 2 x 1 u
= 2 u
Cost of 3 marbles
= 3 x 3 u
= 9 u
Total cost of 2 stickers and 3 marbles
= 2 u + 9 u
= 11 u
11 u = 11
1 u = 11 ÷ 11 = 1
Cost of 1 sticker = 1 u = $1
(b)
Cost of 1 marble
= 3 u
= 3 x 1
= $3
(c)
Cost of 4 marbles and 3 stickers
= 4 x 3 u + 3 x 1 u
= 12 u + 3 u
= 15 u
= 15 x 1
= $15
Answer(s): (a) $1; (b) $3; (c) $15