Question

If the number of telephone calls coming into a telephone exchange between 10 AM and 11 AM follows P.D. with parameter 2, then the probability of obtaining zero calls in that time interval is

• A. $e^{-2}$
• B. $1-e^{-2}$
• C. $2.e^{-2}$
• D. $3.e^{-2}$

Answer 1

Answer: (A)

$e^{-2}$

Here P.D parameter $\lambda =2$
Hence probability of obtaining zero calls during 10 AM to 11 AM is $=\left(P\right(X=0)=e^{-2}$