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CAIE A Level Mathematics 9709 · The normal distribution

The normal distribution: calculation question

4 marksChallenge

The random variable XX is normally distributed with mean μ=90\mu = 90 and standard deviation σ=2000\sigma = 2000. Find the value of xx such that P(X<x)=0.975\mathrm{P}(X < x) = 0.975.

  1. (a)

    Calculate xx.

    [4]

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