Adam pays $27.80 for 1 marble and 5 stickers.
The marble costs $1.40 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 5 marbles and 6 stickers?
(a)
Choose the cheaper item to be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 marble = 1 u + 1.40
Cost of 5 stickers
= 5 x 1 u
= 5 u
Total cost of 1 marble and 5 stickers
= 1 u + 1.40 + 5 u
= 6 u + 1.40
6 u + 1.40 = 27.80
6 u = 27.80 - 1.40
6 u = 26.40
1 u = 26.40 ÷ 6 = 4.40
Cost of 1 marble
= 4.40 + 1.40
= $5.80
(b)
Cost of 5 marbles and 6 stickers
= 5 x 5.80 + 6 x 4.40
= 29.00 + 26.40
= $55.40
Answer(s): (a) $5.80; (b) $55.40