The lonely Dinner
I have six friends and during a vacation,I met them at several dinners. I found that I dinned with all of them exactly once, with every five of them on two days, with every four of them on three days, with every three of them on four days, with every two of them on five days. Each one was present for seven dinners and each missed seven dinners. How many dinners did I have alone?
The answer is 1.
This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try
refreshing the page, (b) enabling javascript if it is disabled on your browser and,
finally, (c)
loading the
non-javascript version of this page
. We're sorry about the hassle.
1 solution
"Each one was present for seven dinners and each missed seven dinners. " This sentence means than there were 14 dinners. One dinner was with all friends. 1) 123456 And there were 5 dinners where only 5 of the friends were present
2) 12345 3) 12346 4) 12356 5) 12456 6) 13456 7) 23456
After these 7 dinners each friend was present on 6 dinners. So must be 6 dinners when he dined with only 1 friend. So only 1 dinner we was alone.