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One lined question on probability?

  • #1
rock.freak667
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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


Homework Equations





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.
 

Answers and Replies

  • #2
CompuChip
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Note that all probabilities should sum to 1...

Does the word "binomial distribution" mean anything to you?
 
  • #3
rock.freak667
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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 :redface:

So basically, the distribution is just X~Bin(6,0.6), except I need to write out the numbers and not just the pdf.
 
  • #4
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.
 
  • #5
rock.freak667
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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
 
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