Urgent help with statistics word problem needed! Maybe Central Limit Theorem?

Hi, I'm a psych major and don't know much about stats. I'm struggling with this practice question, preparing for a test.

70 boxes of a supposed mean 250 pens each have been sent to the office. The company says the standard deviation is 5. Having had a secretary count all the pens, he found that the mean is 232 pens. Should the boss of the office suspect that pen gnomes of some sort are stealing pens?

Re: Urgent help with statistics word problem needed! Maybe Central Limit Theorem?

Hey reallyneedhelpreid.

Hint: Set up the hypothesis that H0: mu >= 250 and H1: mu < 250