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Been looking for help for 2 hrs hopefully you can help

Been looking for help for 2 hrs hopefully you can help-example-1
User Jessel
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1 Answer

23 votes
23 votes

Given:


\begin{gathered} \mu=19.9 \\ \sigma=33.1 \\ n=40 \end{gathered}

To Determine:


P(X>8.9)

Solution


\begin{gathered} P(X>z) \\ z=(x-\mu)/(\sigma)=(8.9-19.9)/(33.1)=(-11)/(33.1)=-0.3323 \end{gathered}
P(X>8.9)=1-P(X<8.9)=1-0.36982=0.63018

Hence, P(x>8.9) = 0.6302 (nearest 4 d. p)

User Adam Morris
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