Question

betty gets paid 25 cents per paper to deliver newspapers in her neihborhood. when betty is sick, she pays her brother bob 10 cents per paper to deliver for her. if bobby makes $7.80 filling in for betty, how much money does betty get to keep for that day?

Answer 1

 cents
( Betty's pay ) - ( what she paid Bobby )

Betty gets to keep $11.70 for the day
( notice that I did all calculations in cents until
the end when I converted to dollars ) 
hope this helps:))