The conversion factor between cup and ounces is that one customary cup contains 8 ounces. The number of mugs (m) that can be filled is the ratio between the available amount of coffee (c) and the volume (v) that the mug can hold.
m = c / v
m = (60 ounces) / (8 ounces / mug) = 7.5 mugs
Thus, you can fill only 7 cups and the 8th cup is only half full.
