What is the mean of x, given the exponential probability function $$f ( x ) = \frac { 1 } { 20 } e ^ { \frac { x } { 20 } } \text { for } x \geq 0 \text { ? }$$
A)0.05
B)20
C)100
D)2,000

Question

Quizplus · Accepted Answer

The mean of an exponential distribution with the probability density function $ f(x) = \frac{1}{\lambda} e^{-\frac{x}{\lambda}} $ is $\lambda$. Here, $\lambda = 20$, so the mean is 20.

What Is the Mean of X, Given the Exponential Probability f(x)=120ex20 for x≥0 ? f ( x ) = \frac { 1 } { 20 } e ^ { \frac { x } { 20 } } \text { for } x \geq 0 \text { ? }f(x)=201​e20x​ for x≥0 ?

What Is the Mean of X, Given the Exponential Probability $f ( x ) = \frac { 1 } { 20 } e ^ { \frac { x } { 20 } } \text { for } x \geq 0 \text { ? }$