The weather is becoming important to you since you would like to go on a picnic today.If it was sunny yesterday,there is a 70% chance it will be sunny today.If it was raining yesterday,there is a 30% chance it will be sunny today.If the probability that it was raining yesterday is 0.25,what is the probability that it will rain today?
A)0.1
B)0.3
C)0.4
D)0.7
E)None of the above

Question

Quizplus · Accepted Answer

The probability it was sunny yesterday is 0.75. The probability it will rain today given it was sunny yesterday is 0.3. The probability it will rain today given it was raining yesterday is 0.7. Using total probability: P(Rain today) = 0.75 * 0.3 + 0.25 * 0.7 = 0.225 + 0.175 = 0.4.

The Weather Is Becoming Important to You Since You Would