Find the probability that it is windy given it is rainy

The probability P(rain and wind) can be expressed as
                       P(R&W) = P(R) * P(W)
Should we use our given information, the following equation can be created and solved.           
                                   0.9 * P(W) = 0.7
                                            P(W) = 0.777
P(W) = 0.78 = 78%. Thus, the answer is 78%