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In: Statistics and Probability

X is normal with a mean of 98 and sigma=12.6. If you take a random sample...

X is normal with a mean of 98 and sigma=12.6. If you take a random sample of 40, find P(Xbar <101).

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Expert Solution

Solution :

Given that ,

mean =   = 98

standard deviation = = 12.6

n = 40

= 98

=  / n =12.6 / 40=1.9922

P( <101 ) = P[( - ) / < (101-98) / 1.9922]

= P(z <1.51 )

Using z table  

=0.9345   

probability= 0.9345   

orchestra answered 2 years ago
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