Question

The number of arrangements of the letters of the word $BANANA$ in which two $N^{\prime }s$ do not appear adjacently is :

• A. $40$
• B. $60$
• C. $80$
• D. $100$

Answer 1

The correct option is A $40$

The total number of words in $BANANA$ is $6$
The total number of arrangement$=\frac{6!}{3!\times 2!}=60$
The number of way in which two $N^{\prime }s$ are together
$=\frac{5!}{3!}=20$
Hence number of way in which two $N^{\prime }s$ do not appear adjacently $=60-20=40$