Hello, KCET rank will be calculated by considering the performances in KCET and Qualifying examination (QE). Let us consider that u have scored 131/180 in KCET and 288/300 in your qualifying exam, then your % marks in KCET is 72.77% and in QE it is 96% now add this two. Depending on the R the KCET ranks are sorted.

Hope it will be helpful for you :)