Question

In: Statistics and Probability

let Y be a random variable . in a population , my=81 and variance =45. use...

let Y be a random variable . in a population , my=81 and variance =45. use central limit theorem th answer n=140 find Prob(Y<82)

Expert Solution

Solution :

Given that ,

mean = = 181

variance = ² = 45

standard deviation = = 45

n = 140

= 81 and

= / n = 45 / 140

P( < 82) = P(( - ) / < (82 - 81 / 45 / 140 ) = P(z < 1.7638)

Using standard normal table,

P( < 82) = 0.9611

orchestra answered 2 years ago

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