Khan/khan-exercises — Issue #7674: Compound inequalities - wrong solution
Author: KhanBugz
Created: 2011-12-03 20:42:32+00:00
State: open
Labels: firefox, win7, wrong-or-unclear

I don't see why the solution is "all real numbers" Indeed, the conditions imly z>1 and z<4 which is not obviously satisfied by all real numbers.

[compound_inequalities.html?seed=182&problem=0](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/compound_inequalities.html?seed=182&problem=0&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/compound_inequalities.html?seed=182&problem=0&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%22%3Ccode%20style%3D%5C%5C%5C%22display%3A%20none%3B%5C%5C%5C%22%3Ez%26gt%3B3%3C%2Fcode%3E%20or%20%3Ccode%20style%3D%5C%5C%5C%22display%3A%20none%3B%5C%5C%5C%22%3Ez%26lt%3B4%3C%2Fcode%3E%5C%22%22%2C145%5D%2C%5B%22incorrect-activity%22%2C%22%5C%22%3Ccode%20style%3D%5C%5C%5C%22display%3A%20none%3B%5C%5C%5C%22%3Ez%26gt%3B1%3C%2Fcode%3E%20or%20%3Ccode%20style%3D%5C%5C%5C%22display%3A%20none%3B%5C%5C%5C%22%3Ez%26lt%3B3%3C%2Fcode%3E%5C%22%22%2C2%5D%2C%5B%22incorrect-activity%22%2C%22%5C%22%3Ccode%20style%3D%5C%5C%5C%22display%3A%20none%3B%5C%5C%5C%22%3Ez%26gt%3B7%3C%2Fcode%3E%5C%22%22%2C6%5D%2C%5B%22correct-activity%22%2C%22%5C%22%3Cspan%20data-else-if%3D%5C%5C%5C%22IS_OR%20%26amp%3B%26amp%3B%20ALL_NUMBERS%5C%5C%5C%22%3EAll%20real%20numbers.%3C%2Fspan%3E%5C%22%22%2C2%5D%5D)

["z>3 or z<4","z>1 or z<3","z>7","All real numbers."]

Mozilla/5.0 (Windows NT 6.1; WOW64; rv:8.0.1) Gecko/20100101 Firefox/8.0.1

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