Khan/khan-exercises — Issue #12046: Counting 2 - there are 8 people in a room
Author: KhanBugz
Created: 2012-01-25 01:44:13+00:00
State: open
Labels: safari, snowleo, wrong-or-unclear

should equal 32 because if each person shakes each other persons hand exactly once than 8 can only shake 7.6.5.4.3.2.1 and 7 can only shake 6.5.4.3.2.1 because it already shook 8's hand and 6 can only shake 5.4.3.2.1 and 5 only 4.3.2.1 and 4 only 3.2.1 and 3 only 2.1 and 2 only 1 because they already shook the previous peoples hands

[counting_2.html?seed=190&problem=handshakes](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/counting_2.html?seed=190&problem=handshakes&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/counting_2.html?seed=190&problem=handshakes&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%2232%5C%22%22%2C48%5D%5D)

["32","32"]

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