Probability of a Mailing Machine

I need some real serious help. This is the problem I need to finish.

A technician services mailing machines at companies in the Phoenix area. Depending on the type of malfunction, the service can take 1,2,3 or 4 hours. The diff. types of malfunctions happens at about the same frequency.

1. Develop a probability distribution for duration of a service call.
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TS Contributor

Thanks for visiting and posting...

You need to show us that you've attempted this problem so that we're not just "doing your homework."

What parts of this have you done so far? What parts are you having difficulty with?

Again, we're happy to help and appreciate you using our service!

Hi NIkNice,

The solution is almost given in the problem. You have X=1,2,3, or 4, and they each have the same probability. The probabilities add up to 1...


TS Contributor
This is exactly like the probability of the different outcomes when you roll a single die.....each outcome =1/6 and their sum =1