Adam pays $29 for 5 stickers and 2 marbles.
2 stickers cost as much as 5 marbles.
- How much is 1 sticker?
- How much is 1 marble?
- How much is 3 marbles and 5 stickers?
(a)
LCM of 2 and 5 = 10
Cost of 2 stickers = 10 u
Cost of 1 sticker = 10 u ÷ 2 = 5 u
Cost of 5 marbles = 10 u
Cost of 1 marble = 10 u ÷ 5 = 2 u
Cost of 5 stickers = 5 x 5 u = 25 u
Cost of 2 marbles = 2 x 2 u = 4 u
Total cost of 5 stickers and 2 marbles
= 25 u + 4 u
= 29 u
29 u = 29
1 u = 29 ÷ 29 = 1
Cost of 1 sticker
= 5 u
= 5 x 1
= $5
(b)
Cost of 1 marble
= 2 u
= 2 x 1
= $2
(c)
Cost of 3 marbles and 5 stickers
= 3 x 2 u + 5 x 5 u
= 6 u + 25 u
= 31 u
= 31 x 1
= $31
Answer(s): (a) $5; (b) $2; (c) $31