Question
In: Statistics and Probability
Sarah scores an 85 on an (IQ) test with a mean of 94 and a standard...
Sarah scores an 85 on an (IQ) test with a mean of 94 and a standard deviation of 10. At what percentile rank is she with respect to the rest of the population?
Please show work- thank you.
Solutions
Expert Solution
µ = 94
σ = 10
left tailed
P( X ≤ 85.000 )
Z =(X - µ ) / σ = ( 85 -
94 ) / 10
Z = -0.900
P(X ≤ 85 ) = P(Z ≤
-0.90 ) = 0.1841
excel formula for probability from z score is
=NORMSDIST(Z)
her percentile is 18.41 th
orchestra answered 1 year agoRelated Solutions
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