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combinatorics
Posted: Sun Aug 02, 2015 6:06 pm
by Mahfuz Sobhan
There are 9 committees with each committee having 20 members and any two committee have 5 members in common then find the minimum number of distinct members in this group.....
Re: combinatorics
Posted: Fri Feb 09, 2018 10:38 pm
by Tasnood
Let $5$ members be common for all $9$ committees [Let they be called VIP]
So, the number of non-VIP members of each committee is=$20-5=15$ and, in total=$15 \times 9=135$
Adding the VIP, the number of total members=$135+5=140$
Re: combinatorics
Posted: Sat Feb 17, 2018 9:25 pm
by M. M. Fahad Joy
Tasnood wrote: ↑Fri Feb 09, 2018 10:38 pm
Let $5$ members be common for all $9$ committees
[Let they be called VIP]
So, the number of
non-VIP members of each committee is=$20-5=15$ and, in total=$15 \times 9=135$
Adding the VIP, the number of total members=$135+5=140$
Sorry, don't understand. Would you please make understand me?
Re: combinatorics
Posted: Sat Feb 17, 2018 10:45 pm
by samiul_samin
Re: combinatorics
Posted: Sat Feb 17, 2018 10:47 pm
by samiul_samin
Re: combinatorics
Posted: Sun Feb 18, 2018 8:18 am
by M. M. Fahad Joy
Thanks a lot.
Re: combinatorics
Posted: Sun Feb 18, 2018 9:48 am
by samiul_samin
M. M. Fahad Joy wrote: ↑Sat Feb 17, 2018 9:25 pm
Tasnood wrote: ↑Fri Feb 09, 2018 10:38 pm
Let $5$ members be common for all $9$ committees
[Let they be called VIP]
So, the number of
non-VIP members of each committee is=$20-5=15$ and, in total=$15 \times 9=135$
Adding the VIP, the number of total members=$135+5=140$
Sorry, don't understand. Would you please make understand me?
You can get many information about combinatorics here
Re: combinatorics
Posted: Sun Feb 18, 2018 10:00 am
by M. M. Fahad Joy
Wow... It is like a whole course in Bangla. The administrators should active these forums all the time.
Re: combinatorics
Posted: Sun Feb 18, 2018 10:09 am
by M. M. Fahad Joy
Here 5 members are common in two committee, not nine.
But why?
Re: combinatorics
Posted: Sun Feb 18, 2018 10:20 am
by samiul_samin
You get wrong.It is two committee it is any two committee.