Question

In how many different ways can the letters of the word 'ALLAHABAD' Be permuted .

Answer 1

There are 11 letters in ${}^{\prime }ALLAHABA{D}^{\prime }$ with $4A^{\prime }s$ and $2L^{\prime }s$.

Number of ways it can be permuted is $11!$

But there are same letters

Hence, the number of ways it can be permuted is $\frac{11!}{4!2!}$