Permo Combo continues 2

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Permo Combo continues 2

by maihuna » Sun Aug 09, 2009 10:00 am
29: Twenty two men arrange to play a cricket match, if two of the men are brothers find out number of ways in which the team can be made up so that the brothers do not play in same side.

!19/!10!11
!19/!10!9
2!19/!10!9
2!21/!11!9
!22/!11!11
Charged up again to beat the beast :)
Source: — Problem Solving |

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by real2008 » Sun Aug 09, 2009 10:59 am
ans is B

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by maihuna » Sun Aug 09, 2009 11:09 am
No ans is not B, anyway give ur logic that is more imp
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Re: Permo Combo continues 2

by real2008 » Sun Aug 09, 2009 11:35 am
maihuna wrote:29: Twenty two men arrange to play a cricket match, if two of the men are brothers find out number of ways in which the team can be made up so that the brothers do not play in same side.

!19/!10!11
!19/!10!9
2!19/!10!9
2!21/!11!9
!22/!11!11
say two teams T1 & T2

Now out of two siblings one can go to team T1 and the rest boy two T2. so this can be done 1way.

So we are left with 20 boys. we need to choose ten out of these 20 boys for t1 (20C10) and then rest of twenty boys i.e. 10 will go to T2 one way.

so number of ways team can be formed is 1 x 20C10 x 1. Now if u solve or rearrange it u will get choice C.