There are 20 students, each has a choice of
anywhere from 0 to 6 courses from a total of 6 courses
offered.
Prove or disprove:
There are 5 students and 2 certain
courses such that all 5 have chosen both courses or all 5
have chosen neither of them.
X---XX
X---XX
X-X--X
X-X--X
X-XX--
X-XX--
XX-X--
XX-X--
XX--X-
XX--X-
-X-X-X
-X-X-X
-XX-X-
-XX-X-
-XX--X
-XX--X
--XXX-
--XXX-
---XXX
---XXX
So disprove. If I do not got lost in the labyrinth...
Just 4 students share any pair of courses and just 4 student miss any pair of courses.
Edited on February 16, 2016, 1:51 am
|
Posted by armando
on 2016-02-15 16:35:24 |