Adam pays $31 for 3 marbles and 5 stickers.
5 marbles cost as much as 2 stickers.
- How much is 1 marble?
- How much is 1 sticker?
- How much is 2 stickers and 3 marbles?
(a)
LCM of 5 and 2 = 10
Cost of 5 marbles = 10 u
Cost of 1 marble = 10 u ÷ 5 = 2 u
Cost of 2 stickers = 10 u
Cost of 1 sticker = 10 u ÷ 2 = 5 u
Cost of 3 marbles = 3 x 2 u = 6 u
Cost of 5 stickers = 5 x 5 u = 25 u
Total cost of 3 marbles and 5 stickers
= 6 u + 25 u
= 31 u
31 u = 31
1 u = 31 ÷ 31 = 1
Cost of 1 marble
= 2 u
= 2 x 1
= $2
(b)
Cost of 1 sticker
= 5 u
= 5 x 1
= $5
(c)
Cost of 2 stickers and 3 marbles
= 2 x 5 u + 3 x 2 u
= 10 u + 6 u
= 16 u
= 16 x 1
= $16
Answer(s): (a) $2; (b) $5; (c) $16