What is the better deal: babysitting for 8 hours and making $72.00 or babysitting for 6 hours and making $57.00

The better deal would be to babysit for 6 hours and making $57.00. 
1. First, I found the unit rate. How much do you make for 1 hour of work? 72/8=9. So, you make $9.00 per hour.
2. Second, I did the same thing with the other situation. 57/6= 9.50. So, you make $9.50 per hour. 
3. The better deal would be to babysit for 6 hours making $57.00 because you are making more money per hour. 9<9.5

Its equal to d=7.07in