Of 18 fast food restaurants in a city, 7 are in violation of sanitary standards, 8 are

Question:

Of 18 fast food restaurants in a city, 7 are in violation of sanitary standards, 8 are in violation of safety standards, and 4 are in violation of both. If a fast food restaurant is chosen at random, what is the probability that it is in compliance with both safety and sanitary standards?