Khan/khan-exercises — pull request #31806 by xymostech (2012-10-14 14:30:12+00:00)
Title: Fix linear equations

Reword the problems so that it actually fits with what the question is asking. Mostly "more than" -> "at least"

Closes #31799 #31638 #31642 #31673 #31710 #31712 #31723 #31753 #31755 #31781 #31782 #31783 #31795 #31799

@beneater