Question 474387
{{{mu = 3}}}

{{{P(X = 4) = e^(-3)*(3^4/4!) = 0.168}}} to 3 decimal places.

{{{P(X = 0) + P(X = 1) + P(X = 2) =  e^(-3)*(3^0/0! + 3^1/1! + 3^2/2!) = 
e^(-3)(1+3 + 4.5) = 8.5e^(-3) = 0.42319}}}, to 5 decimal places.