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    Does anyone know how to find the probability, say P(Z <1), using the above mentioned calculator.

    I have tried STAT DISTR pdfnorm(1) but it comes up with 0.2419.... instead of 0.84134.

    I can't find anything else in the manual.
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    I don't know this calculator, but to find P(Z<1) you need to look for a function that looks like "cdf" (cumulative distribution function) rather than pdf. The pdf function will give you the value of the normal bell curve at Z=1, but that's not P(Z<1), for which you need the cumulative version.
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    (Original post by old_engineer)
    I don't know this calculator, but to find P(Z<1) you need to look for a function that looks like "cdf" (cumulative distribution function) rather than pdf. The pdf function will give you the value of the normal bell curve at Z=1, but that's not P(Z<1), for which you need the cumulative version.
    Thank you. I didn't know what pdf and cdf stood for so that has been a great help in itself. I have now found cdfnorm(lower limit, upper limit [, mean, standard deviation]). when I enter (0,2) it gives me a value that I then need to add 0.5 to for the other half of the curve, as it were. I can live with that as it seems there isn't a function that will give me everything to the left of 2.

    I'll just have to think harder won't I.

    Thanks. Most helpful.
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    You should also be able to include the left hand half of the curve by typing in a large negative number, e.g. -1E6 as your lower limit.
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    Yes, that worked. What a gem you are.
 
 
 
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