Suppose ? is a random variable with mean ?=50 and standard deviation ?=49. A random sample...

Suppose ? is a random variable with mean ?=50 and standard deviation ?=49. A random sample of size ?=38 is selected from this population.

a) Find ?(?¯<49).P(X¯<49). Round your answer to four decimal places.

b) Find ?(X¯≥52).P(X¯≥52). Round your answer to four decimal places.

c) Find ?(49.5≤X¯≤51.5).P(49.5≤X¯≤51.5). Give your answer to four decimal places.

d) Find a value ?c such that ?(X¯>?)=0.15.P(X¯>c)=0.15. Round your answer to two decimal places.

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orchestra answered 1 year ago

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