Answer:
$12
Step-by-step explanation:
Matt makes $80 a month mowing lawns while James also mows lawns and makes x dollars less per month.
That is, the amount that James makes a month is:
80 - x
James makes $816 per year.
Since there are 12 months in a year, this implies that:
(80 - x) * 12 = 816
=> 960 - 12x = 816
960 - 816 = 12x
144 = 12x
=> x = 144 / 12 = $12
James makes $12 less than Matt every month
