Khan/khan-exercises — Issue #13199: Counting 1 - fence posts problem
Author: KhanBugz
Created: 2012-02-06 22:14:00+00:00
State: open
Labels: chrome, win7, wrong-or-unclear

The answer indicated she needed 2 posts - one for each end. This does not appear to be correct. Below is the question - and then the hints:

Ashley is building a straight fence, with posts one meter apart.

If the fence is 15 meters long, how many fence posts does she need?

If the fence is one meter long, she needs two posts (one for each end).

If the fence is two meters long, then she needs three posts, and so on.

[counting_1.html?seed=140&problem=fences](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/counting_1.html?seed=140&problem=fences&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/counting_1.html?seed=140&problem=fences&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5B%5C%2214%5C%22%5D%22%2C24%5D%2C%5B%22incorrect-activity%22%2C%22%5B%5C%2215%5C%22%5D%22%2C2%5D%2C%5B%22incorrect-activity%22%2C%22%5B%5C%2215%5C%22%5D%22%2C11%5D%2C%5B%22hint-activity%22%2C%220%22%2C6%5D%2C%5B%22hint-activity%22%2C%220%22%2C33%5D%5D)

[["14"],["15"],["15"]]

Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.7 (KHTML, like Gecko) Chrome/16.0.912.77 Safari/535.7

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