Answer:
he has to make a sale of $750
Explanation:
first job pays $880 per week
second job pays $790 per week
amount first job is paying more=$(880-790)
=$90
therefore,12% should $90 if he wants to make an equal amount as the first job is paying therefore,sale he has to do
12% of x=$90
12/100*x=$90
x=90*100/12
x=9000/12
x=$750
thus he has to make a sale of $750 to earn a 12% comission of $90