Acompany used about 7.4 x 105 sheets of paper in a month. of the paper used during the month, the accounting department used about 8.9 x 103 of the sheets. about how many sheets of paper were used by other departments during the month?

So (7.4*105)-(8.9*103)   (The sum of all departments)-(The sum of the accounting department) 

(7.4*105)-(8.9*103) = (777)-(916.7) =(-139.7), not sure, did you write the problem wrong? If the total of the company is less than what the account dept used, something is off.  

hope it is correct if not i'm srry i tried to