Distribution of time until all exponential events happen

Rumbo

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"A factory contains 8 machines. These machines can break down independently of the other machines following an exponential distribution with a mean value of 10 years.
What is the distribution of time until all 8 machines break down?"


I understand that the lambda in this situation is 1/10, but the fact that the question is looking for a distribution of time is what is throwing me. Am I correct in thinking that I will be using 8*(1/10) or 8/10 as my lambda for this distribution because it involves all 8 independent machines?

Would that mean that:

[MATH]f(x) =0.8 e^{-0.8x}[/MATH]? This is the time between 8 blowouts right? And is it therefore what the question is asking for? Or should I be looking at the Cumulative density function and working at when the probability =1?

Sorry that I'm unable to fully explain my line of thinking, the fact that it isn't actually asking for a numerical answer and instead a distribution is confusing to me. Any help is greatly appreciated, thanks.
 
Seems the best way to get a response here is to actually not follow the rules, and provide no information other than your question. I'll have to note that for next time...
 
"A factory contains 8 machines. These machines can break down independently of the other machines following an exponential distribution with a mean value of 10 years.
What is the distribution of time until all 8 machines break down?"


I understand that the lambda in this situation is 1/10, but the fact that the question is looking for a distribution of time is what is throwing me. Am I correct in thinking that I will be using 8*(1/10) or 8/10 as my lambda for this distribution because it involves all 8 independent machines?

Would that mean that:

[MATH]f(x) =0.8 e^{-0.8x}[/MATH]? This is the time between 8 blowouts right? And is it therefore what the question is asking for? Or should I be looking at the Cumulative density function and working at when the probability =1?

Sorry that I'm unable to fully explain my line of thinking, the fact that it isn't actually asking for a numerical answer and instead a distribution is confusing to me. Any help is greatly appreciated, thanks.
I also do not quite understand the meaning of "distribution of time" in the context of the given problem. Probably there was no answer to your query because all other volunteer-helpers did not understand it either!

Is this a translated problem? Could you post a photocopy of the original problem - for us to see if there is a different interpretation "hidden" here?
 
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