Question:
In how many ways can 4 women draw water from 4 taps if no tap remains unused?
Solution:
Given: We have 4 women and 4 taps
To Find: Number of ways of drawing water
Condition: No tap remains unused
Let us represent the arrangement
The first woman can use any of the four taps $=4$ Ways
The second woman can use the remaining three taps $=3$ ways
The third woman can use the remaining two taps $=2$ ways
The fourth woman can use the remaining one tap $=1$ way
Total number of ways $=4 \times 3 \times 2 \times 1=24$
There is 24 number of ways in which 4 women can draw water from 4 taps such that no tap remains unused.