Khan/khan-exercises — Issue #14130: Ratio word problems - answer right?
Author: KhanBugz
Created: 2012-02-18 17:16:45+00:00
State: open
Labels: firefox, other, win7

The scale on a map is 7cm : 9km.

If two cities are 70cm apart on the map, what is the actual distance in km between the two cities?

The scale means that every 7cm on the map corresponds to an actual distance of 9km.

A distance of 70cm on the map is the same as 10 ⋅ 7cm.

The actual distance between the two cities is 10 ⋅ 9km, or 90km.

I entered 90km

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

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/ratio_word_problems.html?seed=190&problem=map&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5B%5C%2290km%5C%22%5D%22%2C133%5D%2C%5B%22hint-activity%22%2C%220%22%2C1%5D%2C%5B%22hint-activity%22%2C%220%22%2C6%5D%2C%5B%22hint-activity%22%2C%220%22%2C11%5D%5D)

[["90km"]]

Mozilla/5.0 (Windows NT 6.1; rv:10.0.1) Gecko/20100101 Firefox/10.0.1

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