Clearly indicate the necessary steps,including appropriate formula substitutions,diagrams,graphs,charts,etc.
Abe,Brian,and Carmela share the responsibility of caring for the family pets. During a seven-day week, Abe and Brian each take three days and Carmela the other one. In how many different orders can the days of a week be assigned.
pretend to write ABE, ABE, ABE, BRIAN,BRIAN, BRIAN, and CARMELA
on pieces of paper and arranging them in a row of 7 places, (the days of the week)
Wouldn't that just be 7!/(3!3!) ??
or 140 ways