# Probability (Poisson)

• Dec 16th 2009, 04:05 PM
nameck
Probability (Poisson)
A machine on average produces 4 defective items out of a batch of 100 items.
Find the probability that a batch of 50 items has 3 defective items in it using the Poisson probability distribution.

the problem is..
i just want to know the mean or average value for batch of 50 items..
i got mean = 2
because for 100 items, the mean is 4..
............for 50 items, the mean would be 2..
correct?
• Dec 16th 2009, 06:51 PM
mr fantastic
Quote:

Originally Posted by nameck
A machine on average produces 4 defective items out of a batch of 100 items.
Find the probability that a batch of 50 items has 3 defective items in it using the Poisson probability distribution.

the problem is..
i just want to know the mean or average value for batch of 50 items..
i got mean = 2
because for 100 items, the mean is 4..
............for 50 items, the mean would be 2..
correct?

Yes.
• Dec 16th 2009, 07:00 PM
nameck
Thanks for the confirmation mr fantastic! (Rofl)