SOLUTION: 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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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) About Me  (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) About Me  (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)