Home » Aptitude » Permutation and Combination

How many three digit numbers 'abc' are formed where two of the three digits are same ?

Correct Answer: 243

Explanation:

Digits are 0,1,2,3,4,5,6,7,8,9. So no. of digits are 10


 


First all possible case => 9(0 excluded) x 10 x 10 = 900


 


Second no repetition allowed =>9 x 9 x 8 = 648


 


Third all digits are same => 9 (111,222,333,444,555,666,777,888,999)


 


Three digit numbers where two of the three digits are same = 900 - 648 - 9 = 243 ;


← Previous Question Next Question→

More Questions from Permutation and Combination

Discussion & Comments

No comments yet. Be the first to comment!
Join Discussion