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The mean and standard deviation of a normal distribution is given(mean=18 and standard deviation=2.5). We have to find the value of k for which P(X<k)=0.2578. It's exhausting to look for the value of z for which the area is 0.2578 from the normal integral table. So how can I find inverse normal in calculator (fx-991ms)?
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$\begingroup$It's exhausting to look for the value of z for which the area is 0.2578 from the normal integral table
really? it is enough to find the quantile of $1-0.2578=0.7422$ and take the opposit value:
Result:-0.65
(quicker than pressing a complicated key's combination on a calculator...and works also in a battery low situation)
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