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Continuous random variables and the normal distribution — Question 190

Original QCE Vault practice · 5 marks

Q190 · Practice questionTechnology-activeComplex unfamiliar5 marks

QUESTION 190 (5 marks)

A normal random variable XX satisfies P(X<68)=0.05P(X<68)=0.05 and P(X>82)=0.20P(X>82)=0.20. Determine the mean and standard deviation of XX to three significant figures.
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