web2.0calc
 
+0  
 

 need help..

0
455
1
avatar

I run a coffee club with n people, not including myself. Every day, for 365 days, I invite four members in the club to have coffee with me. What is the smallest positive integer n so that I can avoid having the same group of four members over all 365 days?

 Jan 11, 2020

1+0 Answers

 #1
avatar
+1

Not counting yourself, in order to have a DISTINCT group of 4 people, you would have at least 12 people, because: 11 C 4 =330  Distinct combinations of 4 people. You need a minimum of 365. Therefore:

12 C 4 =495 Distinct combinations, which would be the minimum n.

 Jan 11, 2020

6 Online Users

avatar
avatar
avatar

Top Users

avatar+128408 CPhill moderator
avatar+118608 Melody moderator
avatar+33615 Alan moderator
avatar+14905 asinus moderator
avatar+9519 MaxWong
avatar+3144 admin administrator
avatar+2440 GingerAle
avatar+1763 tomtom
avatar+1484 bader
avatar+1037 parmen
avatar+1030 blackpanther

Sticky Topics