Shen the trainer has two solo workout plans that he offers his clients: plan a and plan b. each client does either one or the other (not both). on friday there were 3 clients who did plan a and 5 who did plan b. on saturday there were 6 clients who did plan a and 2 who did plan b. shen trained his friday clients for a total of 10 hours and his saturday clients for a total of 10hours. how long does each of the workout plans last?