If the random variable X is exponentially distributed with parameter $\lambda$ = 4, then the probability P(X $\leq$ 0.25), up to 4 decimal places, is:
A)0.6321.
B)0.3679.
C)0.2500.
D)None of these choices are correct.

Question

Quizplus · Accepted Answer

The cumulative distribution function (CDF) for an exponential distribution is $1 - e^{-\lambda x}$. Substituting $\lambda = 4$ and $x = 0.25$, we get $1 - e^{-4 \times 0.25} = 1 - e^{-1} \approx 0.6321$.

If the Random Variable X Is Exponentially Distributed with Parameter λ\lambdaλ

If the Random Variable X Is Exponentially Distributed with Parameter $\lambda$