In how many ways can 6 women draw water from 6 wells if no well remains unused?

To find: number of arrangements of 6 women drawing water from 6 wells

Here, 6 wells are needed to be used by 6 women.

Therefore any one of the 6 women can draw water from the 1 well.

Similarly, any 5 women can draw water from the 2^nd well and so on.

Lastly, there will be single women left to draw water from the 6^th well.

Formula:

Number of permutations of n distinct objects among r different places, where repetition is not allowed, is

P(n,r) = n!/(n-r)!

Therefore, permutation of 6 different objects in 6 places is

P(6,6) =

= = = 720.

Hence, this can be done in 720 ways.