At a shop, Erika paid $22 for 1 marble and 8 buttons. The marble cost $4 more than each button.
- How much is 1 button?
- How much is 1 marble?
(a)
Cost of 1 button = 1 u
Cost of 8 buttons = 8 u
Cost of 1 marble = 1 u + 4
Total cost of 1 marble and 8 buttons
= 8 u + 1 u + 4
= 9 u + 4
9 u + 4 = 22
9 u = 22 - 4
9 u = 18
1 u = 18 ÷ 9 = 2
Cost of 1 button
= 1 u
= $2
(b)
Cost of 1 marble
= 1 u + 4
= 2 + 4
= $6
Answer(s): (a) $2; (b) $6