At a shop, Abi paid $77 for 1 button and 4 pens. The button cost $7 more than each pen.
- How much is 1 pen?
- How much is 1 button?
(a)
Cost of 1 pen = 1 u
Cost of 4 pens = 4 u
Cost of 1 button = 1 u + 7
Total cost of 1 button and 4 pens
= 4 u + 1 u + 7
= 5 u + 7
5 u + 7 = 77
5 u = 77 - 7
5 u = 70
1 u = 70 ÷ 5 = 14
Cost of 1 pen
= 1 u
= $14
(b)
Cost of 1 button
= 1 u + 7
= 14 + 7
= $21
Answer(s): (a) $14; (b) $21