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splashpot
03-15-2006, 08:32 AM
I hope this is allowed. I have a take home midterm that I need finish in the next few hours, but I'm totally stuck on one of these problems. I was hoping someone could point me in the right direction. Hopefully I'll get a response in time. Here it is.

Certain electronic components has a lifetime T which are exponential random variables with E[T]=5years. A machine is built using two such components. The machine is built so that it uses the first component until it fails, then switches to the second component. When the second component fails, the machine fails and we let M denote the lifetime of the machine. What is the probability that M is less than or equal to 10?

Now I'm pretty sure I have to take the double integral of the joint distribution function, but I'm not sure what parameters to use and such. If anyone is able to give me a few hints, I'd appreciate it.
cambraceres
03-15-2006, 10:27 AM
Should be posted in SMP, I'm sure Bruce or someone can help.
splashpot
03-15-2006, 10:33 AM
[ QUOTE ]
Should be posted in SMP, I'm sure Bruce or someone can help.

[/ QUOTE ]
/images/graemlins/confused.gif /images/graemlins/confused.gif /images/graemlins/confused.gif SMP isn't Science, Math and Philosophy? That is where I posted it.
cambraceres
03-15-2006, 11:08 AM
True True don't worry about me, it's the drugs

clock is tickin for ya tho
BruceZ
03-15-2006, 12:07 PM
[ QUOTE ]
I hope this is allowed. I have a take home midterm that I need finish in the next few hours, but I'm totally stuck on one of these problems. I was hoping someone could point me in the right direction. Hopefully I'll get a response in time. Here it is.

Certain electronic components has a lifetime T which are exponential random variables with E[T]=5years. A machine is built using two such components. The machine is built so that it uses the first component until it fails, then switches to the second component. When the second component fails, the machine fails and we let M denote the lifetime of the machine. What is the probability that M is less than or equal to 10?

Now I'm pretty sure I have to take the double integral of the joint distribution function, but I'm not sure what parameters to use and such. If anyone is able to give me a few hints, I'd appreciate it.

[/ QUOTE ]

See my response here (http://forumserver.twoplustwo.com/showthreaded.php?Cat=0&Number=5070407&an=0&page=0# Post5070407).