if we want the probability of two events happening at the same time, we multiply the probabilities of each event together. the word "and" tips you off to this kind of probabiliy. (if it said "or" you would add the probabilities)

probability that it will be cloudy tomorrow = 0.6

probability it will rain if it gets cloudy = 0.7

probability that it will be cloudyandrain tomorrow = 0.6*0.7 = 0.42