In a shop, there are 10 kinds of postcards. We want to send postcards to 5 friends. Suppose we want to send two differen
Posted: Sun Sep 05, 2021 5:22 pm
In a shop, there are 10 kinds of postcards. We want to send
postcards to 5 friends. Suppose we want to send two different cards
to each of them, and no two people can receive the same kind of
postcard. In how many different ways can this be done?
postcards to 5 friends. Suppose we want to send two different cards
to each of them, and no two people can receive the same kind of
postcard. In how many different ways can this be done?