Katherine works flexible hours. This month she worked a total of 60 hours, which was 3 more than 5 times as many hours as she worked last month. How many hours did she work last month?

Let x be the number of hours Katherine worked last month.

This month Katherine worked 5*x+3 hours.
And 5*x+3=60.
So 5*x=57.
Thus x=<<57/5=11.4>>11.4. Answer: \boxed{11}.