Adam pays $34.10 for 1 marble and 8 stickers.
The marble costs $2.60 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 8 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 + 2.60
Cost of 8 stickers
= 8 x 1 u
= 8 u
Total cost of 1 marble and 8 stickers
= 1 u + 2.60 + 8 u
= 9 u + 2.60
9 u + 2.60 = 34.10
9 u = 34.10 - 2.60
9 u = 31.50
1 u = 31.50 ÷ 9 = 3.50
Cost of 1 marble
= 3.50 + 2.60
= $6.10
(b)
Cost of 8 marbles and 2 stickers
= 8 x 6.10 + 2 x 3.50
= 48.80 + 7.00
= $55.80
Answer(s): (a) $6.10; (b) $55.80