In a book shop, 4 staplers and 5 notebooks cost $28.30. Joseph bought 5 staplers and 6 notebooks at $34.50 from the book shop.
- Find the cost of 1 stapler and 1 notebook.
- What was the cost of 1 notebook?
(a)
Let 1 stapler be 1 S.
Let 1 notebook be 1 N.
4 S + 5 N = 28.30 --- (1)
5 S + 6 N = 34.50 --- (2)
(2) - (1)
1 S + 1 N = 34.50 --- 28.30
1 S + 1 N = 6.20 --- (3)
Cost of 1 stapler and 1 notebook = $6.20
(b)
(3)
x4 4 S + 4 N = 24.80 --- (4)
(1) - (4)
1 N = 28.30 - 24.80 = $3.50
Cost of 1 notebook = $3.50
Answer(s): (a) $6.20; (b) $3.50