Mia likes changing her exercise routines every week. this week she decides to have three yoga days and four aerobics days. in how many different ways can she schedule yoga and aerobics for the week? one possible schedule is "yoga - mon, wed, sat; aerobics - tue, thu, fri, sun". max prefers wearing neutral colors at work. he is shopping for shirts at wal-mart. the shirts he likes are offered in three neutral colors - white, black, and grey. in how many ways can he select 7 shirts? one possibility is "4 black shirts, 3 white shirts, and 0 gray shirts".