Question

In how many ways can the letters of the word COMPUTER be arranged in a row if the letters C and O can not stand next to each other

Answer 1

35280ways

Explanation:

let X be the number of ways the letters can be arranged with no restriction,

let M be the number of ways they can be arranged if the letters C and O must stand together,

and let the number of ways the letters C and O can be arranged if they can not stand together.

X=8!

M= 7!

N=X–M=8!–7!=35280 ways