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How many even 6 digits nos can be formed with the digits 1,2,3,4,5,6,7 with no repetition n with an even no always in the 2nd last position?
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even 6 digit nos...so last place can be filled up in 3 ways i.e 2,4 & 6
2nd last position is an even no...so it can be filled up in 2 ways...no repetition allowed...
3rd place in 5 ways
4th in 4 ways
5th in 3 ways
6th in 2 ways
So answer is 3*2*5*4*3*2=720...
am i ri8 ???
- 12 years agoHelpfull: Yes(15) No(4)
- ans:2160
1st position no.of choices 6
2nd position no.of choices 5
3rd position no.of choices 4
4th position no.of choices 3
2nd position no.of choices 3
1st position no.of choices 2
6*5*4*3*3*2=2160 - 12 years agoHelpfull: Yes(7) No(3)
- 6 digit even no:last digit is even
5th position is even
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1 2 3 4 5 6
MY english is not good please adjust....
5th position can be filled by 2,4,6 in 3 ways
6th position can be filled by only remaining even numbers since no repetition is allowed i.e.. 2 ways
and 1st place in 5 ways
2nd place in 4 ways(since no repetition is allowed)
3rd place in 3 ways(since no repetition is allowed)
4th place in 2 ways(since no repetition is allowed)
so total number of ways=5*4*3*2*3*2===720 ways - 12 years agoHelpfull: Yes(5) No(2)
- for last 2 digits having even no(in 2 4 6)=3! ways
rest 4 digits will have ways(now 5 no.remains)=5! ways
so total ways being 6 digit even no.=3!*5!=720 - 12 years agoHelpfull: Yes(1) No(2)
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