What is the weather probability? I checked similar threads and understood one thing from them, but I need some help with this problem. "A newspaper presents the weather in this form. Linn, Maria and Victoria discuss the weather that's going to happen tomorrow": Weather : Chance(%) Rain : 40% Cloudy : 70% Hail : 10% Storm : 5% Strong wind : 40% Maria says that the risk of a storm and hail is 15%. Linn says that the chance of it not raining is 60%. Victoria says the weather form is wrong because the sum of all the chances is larger than 100%. "How do the girls think ?, Does anyone think wrong about the weather ?" So here's what I've done: I know that the probability of the hail and storm is: 0,1*0,05 = 0,005 = 0,5% How do I calculate the chance of it not raining, and does Victoria think right ?

Maria is certainly wrong, since the chance of a storm and hail is at most the chance of a storm (5%). Linn is right. Victoria is wrong, the events are not mutually exclusive.

I would certainly not assume independence here.