Approximate Probability problem and I can't figure it out!

[MZb5]

Suppose we have the following facts about customers buying alcohol at the Liquor Mart:
• 55% buy wine (W).
• 40% buy beer (B).
• 22% buy wine and beer.
• 6% buy wine and vodka (V).
• 5% buy beer and vodka.
• 50% buy beer or vodka.
• 2% buy wine and beer and vodka.
More info: 15% buy Vodka

Question: In a random sample of 300 customers, what is the approximate probability that less than 38% of them buy beer? (A) 0.1492 (B) 0.1736 (C) 0.2177 (D) 0.2389 (E) 0.2929

Can someone show me the workings? I've been looking through my notes and online but I just cannot figure it out.

 

[Dr.Peterson]

What methods have you been taught recently, that might be applicable? Maybe the normal approximation to the binomial distribution?

Then at least tell us how you think you might start (just the beginning). That will give us something specific to talk about.