Camila and Evelyn work at a dry cleaners ironing shirts. Camila can iron 40 shirts per hour, and Evelyn can iron 20 shirts per hour. How many total shirts would be ironed between the two workers if Camila worked 6 hours and Evelyn worked 9 hours on a given day? How many total shirts would be ironed between the two workers if Camila worked x hours and Evelyn worked y hours on a given day?