# One lined question on probability?

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One lined question on probability??

## Homework Statement

A worker's record shows 60% of his projects are completed on time. If this performance prevails, write the distribution of X=the number of jobs completed in the next 6 jobs. Find the mean and variance of X

## The Attempt at a Solution

I think that from x=1-6, P(X=x)= 0.6 ? I mean that was all I was given, there is no reason to think otherwise. Is there? Assuming I am correct, I can easily find the mean and the variance.

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CompuChip
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Note that all probabilities should sum to 1...

Does the word "binomial distribution" mean anything to you?

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Note that all probabilities should sum to 1...

Does the word "binomial distribution" mean anything to you?
ahhhh...I was so caught up in trying to make it uniform distribution

So basically, the distribution is just X~Bin(6,0.6), except I need to write out the numbers and not just the pdf.

CompuChip
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Yes, although it would be nice if you showed why it is binomial. I.e., that it satisfies the properties that a binomial experiment has.

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Yes, although it would be nice if you showed why it is binomial. I.e., that it satisfies the properties that a binomial experiment has.
The workers 6 projects are independent and the worker can have 0-6 (k) successes (with each success being a constant)

So X~Bin(n,p) = nCkpk(1-p)n-k