# Poisson Formula finding lamina?

A microprocessor manufacturing facility produces 300 microprocessors per hour. The probability that an individual chip is faulty is 0.01. Calculate the probability that in a given hour's production:

a) Two chips are faulty

To find $$\lambda$$ I multiply

0.01*300 = 3


I am not sure though if I have to take the time into account(1 hour(60))?

Or if the question takes this into account.

Then finding P(2 microchips)

$$3^2$$* $$e^{-3}$$ / 2! = .22

But this seems awfully high to me 22% are my calculations off??

• You have $300 \times 0.01$ as the rate per hour, so do you not have to take into account the "one hour" or if you do then multiply by $1$. If you had wanted rate per day ($24$ hours) then it would be $300 \times 0.01 \times 24$ – Henry Dec 5 '19 at 13:21
• This is what I though thanks, but The final .22 seems very high to me dont you think? – Liam Dec 5 '19 at 13:27
• $0.224$ looks fine to me. By the way, the Greek letter is called lambda rather than lamina and is written $\lambda$ – Henry Dec 5 '19 at 13:31
• Cool thanks @Henry I have made the edits :) – Liam Dec 5 '19 at 13:35