My question is how to calculate the probability density function (pdf) of consequent, but otherwise independent events, defined as follows (in case of 3 events):
$A$ is an independent event with pdf $f(x)=\lambda_1 e^{-\lambda_1x} $.
$P(B|A')=0$, $B|A$ is event with pdf $f(x)=\lambda_2 e^{-\lambda_2x} $.
$P(C|B')=0$, $P(C|B)$ is event with pdf $f(x)=\lambda_3 e^{-\lambda_3x} $.
I understand that for independent events I would need to apply convolution, but I could not find the way to solve the problem for consecutive events.
Note (in case I defined the problem unclearly): once the previous event has occured, the next event becomes an independent event with a defined pdf. Each event can happen only once.