Question 857330:  IQ scores of adults are normally distributed with a mean of 100 and a standard deviation of 15. Find the probability that iq score is less than 88  
 Found 2 solutions by  stanbon, ewatrrr: Answer by stanbon(75887)      (Show Source): 
You can  put this solution on YOUR website! IQ scores of adults are normally distributed with a mean of 100 and a standard deviation of 15. Find the probability that iq score is less than 88  
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z(88) = (88-100)/15 = -12/15 = -4/5 
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P(x< 88) = P(z < -4.5) = binomcdf(-100,-4/5) = 0.2119 
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Cheers, 
Stan H. 
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 Answer by ewatrrr(24785)      (Show Source): 
You can  put this solution on YOUR website!   
Hi, 
TI syntax is normalcdf(smaller, larger, µ, σ). 
P(x < 88) normalcdf(-999,88,100,15)    
Note: -999 used as the smaller value to be at least 5 standard deviations from the mean
 
Or Using z-value 
P(x < 88) = NORMSDIST((88-100)/15)  
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