A box of chalk and 2 staplers cost $10. Three boxes of chalk and 2 staplers cost $18. Find the total cost of 1 box of chalk and 1 stapler.

Answer 1

staples = s
chalk = c

c + 2s = 10
3c + 2s = 18

-c-2s = -10
3c + 2s = 18

2c = 8

c = 4
s = 3

c + s

4 + 3 = 7
The total cost $7.