Khan/khan-exercises — Issue #14070: Counting 2 - How many handshakes occurred
Author: KhanBugz
Created: 2012-02-17 15:12:25+00:00
State: open
Labels: chrome, hard, xp

I don't understand the process behind figuring this out.

[counting_2.html?seed=64&problem=handshakes](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/counting_2.html?seed=64&problem=handshakes&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/counting_2.html?seed=64&problem=handshakes&debug&activity=%5B%5B%22hint-activity%22%2C%220%22%2C22%5D%2C%5B%22incorrect-activity%22%2C%22%5C%2290%5C%22%22%2C62%5D%2C%5B%22hint-activity%22%2C%220%22%2C11%5D%2C%5B%22hint-activity%22%2C%220%22%2C23%5D%2C%5B%22hint-activity%22%2C%220%22%2C35%5D%2C%5B%22correct-activity%22%2C%22%5C%2245%5C%22%22%2C57%5D%5D)

["90","45"]

Mozilla/5.0 (Windows NT 5.1) AppleWebKit/535.11 (KHTML, like Gecko) Chrome/17.0.963.46 Safari/535.11

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