if a coin with a coming up head 0.65 is flipped 50 times, what is the probability it will come up heads 25 times or fewer times?

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Every year, an insurance company writes policy for new license driver. If 40% of these drivers are low risk drivers, 40% are moderate risk and 20% are high risk. the company cannot determine which gropes each driver falls in when they write the policies. So, none of the low rick drivers will have an at fault accident in the next year however 10% of the moderate driver and 20% of the high-risk drivers will have an accident. If there is an as fault accident in the next year, what is the probability that that individual is a high risk