Adam pays $38.10 for 1 marble and 5 stickers.
The marble costs $1.50 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 5 marbles and 3 stickers?
(a)
Choose the cheaper item to be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 marble = 1 u + 1.50
Cost of 5 stickers
= 5 x 1 u
= 5 u
Total cost of 1 marble and 5 stickers
= 1 u + 1.50 + 5 u
= 6 u + 1.50
6 u + 1.50 = 38.10
6 u = 38.10 - 1.50
6 u = 36.60
1 u = 36.60 ÷ 6 = 6.10
Cost of 1 marble
= 6.10 + 1.50
= $7.60
(b)
Cost of 5 marbles and 3 stickers
= 5 x 7.60 + 3 x 6.10
= 38.00 + 18.30
= $56.30
Answer(s): (a) $7.60; (b) $56.30