Khan/khan-exercises — Issue #5875: Counting 2 - Error in "Counting 2"
Author: KhanBugz
Created: 2011-11-09 17:14:37+00:00
State: open
Labels: chrome, vista

Reporter: tka@gladkristen.dk

There are 5 people in a room.

If everyone shakes everyone else's hand exactly once, how many handshakes occurred?

Given 5 people, each person shakes the hands of 4 other people.

The following is almost the answer.

5×4=20

And I answered 20 (multiple times) and was told it was wrong. I even tried 40

But 10 makes it happy - not me though

[counting_2.html?seed=142&problem=handshakes](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/counting_2.html?seed=142&problem=handshakes&debug)

["20","40","40","20","20","10"]

Mozilla/5.0 (Windows NT 6.0; WOW64) AppleWebKit/535.2 (KHTML, like Gecko) Chrome/15.0.874.106 Safari/535.2

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