Q. 14.4( 95 Votes )

# How many 3-digit numbers can be formed by using the digits 1 to 9 if no digit is repeated?

Answer :

Total no. of digits possible for choosing = 9

No. of places for which a digit has to be taken = 3

As there is no repetition allowed;

⇒ No. of permutations =

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Which of the following are true :

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

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