Question : A petrol pump proprietor sells worth Rs. 80,000 on a rainy day and worth Rs.95,000 n a clear day. Statistic from the Meteoroigical Department show that the probability is 0.76 for clear wether and 0.34 for rainy weather on coming Monday. Find the expected value of petrol sale on Monday .

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I have used the Bayes theorem to find the Probability but don't know if its the right method or no.And should I be just using the expected value for this probability or no .....