I had this question on a test:

The probability of snowing in one city is 0.4, and the probability of snowing in another city is 0.7. Assume independence. What is the probability that it snows inexactly oneof the two cities?

The way I approached it was to say that the probability that it snows inexactly oneof the two cities is:

Let A denote probability of snow in the first city.

Let B denote probability of snow in the second city.

P(A and 'not B') or P('not A' and B) = (0.4)(0.3) + (0.6)(0.7) - (0.4)(0.3)(0.6)(0.7) = 0.4896

Is this correct?