Adam pays $25.80 for 1 marble and 4 stickers.
The marble costs $1.30 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 4 marbles and 2 stickers?
(a)
Choose the cheaper item to be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 marble = 1 u + 1.30
Cost of 4 stickers
= 4 x 1 u
= 4 u
Total cost of 1 marble and 4 stickers
= 1 u + 1.30 + 4 u
= 5 u + 1.30
5 u + 1.30 = 25.80
5 u = 25.80 - 1.30
5 u = 24.50
1 u = 24.50 ÷ 5 = 4.90
Cost of 1 marble
= 4.90 + 1.30
= $6.20
(b)
Cost of 4 marbles and 2 stickers
= 4 x 6.20 + 2 x 4.90
= 24.80 + 9.80
= $34.60
Answer(s): (a) $6.20; (b) $34.60