Adam spends $15.40 on 2 stickers and 3 marbles.
A sticker costs 2 times as much as 1 marble.
- How much does 1 sticker cost?
- How much do 4 stickers cost?
- How much do a marble and 4 stickers cost?
- How much does 1 marble cost less than 4 stickers?
(a)
Let the cheaper item be 1 u.
Cost of 1 marble = 1 u
Cost of 1 sticker = 2 u
Cost of 2 stickers = 2 x 2 u = 4 u
Cost of 3 marbles = 3 x 1 u = 3 u
Total cost of 2 stickers and 3 marbles
= 4 u + 3 u
= 7 u
7 u = 15.40
1 u = 15.40 ÷ 7 = 2.20
Cost of 1 sticker
= 2 u
= 2 x 2.20
= $4.40
(b)
Cost of 4 stickers
= 4 x 4.40
= $17.60
(c)
Cost of 1 marble and 4 stickers
= 2.20 + 17.60
= $19.80
(d)
Cost of 1 marble less than 4 stickers
= 17.60 - 2.20
= $15.40
Answer(s): (a) $4.40; (b) $17.60; (c) $19.80; (d) $15.40
