If X is normally distributed random variable with a standard deviation of 16. Find the mean given P(X<420)=0.7.
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If X is
mean given P(X<420)=0.7.
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- CNNBC recently reported that the mean annual cost of auto insurance is 973 dollars. Assume the standard deviation is 234 dollars. You take a simple random sample of 61 auto insurance policies. Find the probability that a single randomly selected value is less than 991 dollars.P(X < 991) = Find the probability that a sample of size n=61n=61 is randomly selected with a mean less than 991 dollars.P(M < 991) =Suppose x has a distribution with a mean of 80 and a standard deviation of 45. Random samples of size n = 36 are drawn. Find P(x < 87.5) Please show the steps to finding the answer and use a ti-83+ calculator since this is what I am working with.
