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Continuous random variables and the normal distribution — Question 139

Original QCE Vault practice · 5 marks

Q139 · Practice questionTechnology-freeComplex familiar5 marks

QUESTION 139 (5 marks)

A continuous random variable has density f(x)=kxf(x)=kx for 0≤x≤30\le x\le3 and f(x)=0f(x)=0 otherwise. Determine kk, E(X)E(X) and the standard deviation of XX.
Triangular probability density increasing linearly from zero at x equals 0 to two-thirds at x equals 3.
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