Q. 144.0( 5 Votes )

# In how many ways can the letters of the word “PENCIL” be arranged so that I is always next to L.

Answer :

There are six letters in **PENCIL** i.e. P, E, N, C, I, L.

Now for I to be next to L,

Consider **LI** to be a letter.

So, there are 5 letters in total now.

So, these five letters can be arranged in ^{5}P_{5} ways.

As we know 0! = 1.

So,

= 5!

= 5× 4× 3× 2× 1

= 120 ways

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Which of the following are true :

(2 + 3)! = 2! + 3!

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