Question
The amount of rainfall (in inches) on a tropical island in the monthof August is a continuous random variable with probability density function $$f(x)=\frac{1}{36} x(6-x) \quad(0 \leq x \leq 6)$$ What is the expected amount of rainfall on any day in August on that island? Find the variance and standard deviation.
Step 1
The expected value is calculated as the integral of x times its probability density function. In this case, the expected value is given by: $$E[X] = \int_{0}^{6} x \cdot f(x) \, dx = \int_{0}^{6} x \cdot \frac{1}{36} x(6-x) \, dx = 4.$$ Show more…
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