Adam pays $37.70 for 1 marble and 5 stickers.
The marble costs $2.30 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 5 marbles and 8 stickers?
(a)
Choose the cheaper item to be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 marble = 1 u + 2.30
Cost of 5 stickers
= 5 x 1 u
= 5 u
Total cost of 1 marble and 5 stickers
= 1 u + 2.30 + 5 u
= 6 u + 2.30
6 u + 2.30 = 37.70
6 u = 37.70 - 2.30
6 u = 35.40
1 u = 35.40 ÷ 6 = 5.90
Cost of 1 marble
= 5.90 + 2.30
= $8.20
(b)
Cost of 5 marbles and 8 stickers
= 5 x 8.20 + 8 x 5.90
= 41.00 + 47.20
= $88.20
Answer(s): (a) $8.20; (b) $88.20