I set this up as a ratio because I personally feel it's easier that way. I put percentages on top and number of passes on the bottom to get [tex] \frac{60}{90} = \frac{100}{x} [/tex]. Of course since those are percents we will use the decimal form of each to get [tex] \frac{.6}{90} = \frac{1}{x} [/tex]. Cross multiply to get .6x = 9 and x = 150
