A group of n families, each with m members, are to be lined up for a photograph. In how many ways can the nm people be arranged if members of a family must stay together? Solution first we have treat each family as one chunk. so we have n chunks to arrange. = n! ways next for each family we can shuffle within family = m! ways for each family. = m! ^ n ways putting them together. n! (m!) ^n ways.

1. A group of n families, each with m members, are to be lined up for a photograph. In how many
ways can the nm people be arranged if members of a family must stay together?
Solution
first we have treat each family as one chunk. so we have n chunks to arrange. = n!
ways next for each family we can shuffle within family = m! ways for each family. = m! ^ n
ways putting them together. n! (m!) ^n ways