Let XXX have PDF f(x)=λe−λxf(x) = \lambda e^{-\lambda x}f(x)=λe−λx for x≥0x \ge 0x≥0. What is the median mmm such that P(X≤m)=0.5P(X \le m) = 0.5P(X≤m)=0.5?
ln2λ\frac{\ln 2}{\lambda}λln2
1λ\frac{1}{\lambda}λ1
12λ\frac{1}{2\lambda}2λ1
2λ\frac{2}{\lambda}λ2