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Statistics 2 - Normal as approx to Poisson

Accidents occur in a factory at an average rate of 5 per month. Find the probability that there will be exactly 62 in a year.

I don't understand how to structure the working out for when it equals something as opposed to greater/less than or equal to, help please??
Original post by timsiu98
Accidents occur in a factory at an average rate of 5 per month. Find the probability that there will be exactly 62 in a year.

I don't understand how to structure the working out for when it equals something as opposed to greater/less than or equal to, help please??


P(less than/equal to 62) - P(less than/equal to 61)?
Reply 2
Original post by chumps52
P(less than/equal to 62) - P(less than/equal to 61)?


but for normal distribution aren't I supposed to include 62.5 and 61.5 or something, I just tried it with 62 and 61 and its not right according to the answer in the back of the book
Original post by timsiu98
but for normal distribution aren't I supposed to include 62.5 and 61.5 or something, I just tried it with 62 and 61 and its not right according to the answer in the back of the book


Have you tried repeating the above but with those two values then? I need to revise stats...
Reply 4
Original post by chumps52
Have you tried repeating the above but with those two values then? I need to revise stats...


Yeah I have tried that but I think I'm missing something lool not sure what though :frown:
Reply 5
http://www.cos.edu/faculty/georgew/tutorial/Pois15.GIF

I would just use that formula and put the number of successes as 62 and the mean as 60 (per year) but given how much I suck at Statistics as is evident from my numerous posts here, that could be a shocking abuse of the formula and a wholly incorrect answer. But that is what I'd do presently.
Reply 6
Original post by djpailo
http://www.cos.edu/faculty/georgew/tutorial/Pois15.GIF

I would just use that formula and put the number of successes as 62 and the mean as 60 (per year) but given how much I suck at Statistics as is evident from my numerous posts here, that could be a shocking abuse of the formula and a wholly incorrect answer. But that is what I'd do presently.


comes up as a maths error cos the number is too big for the calculator haha, I'll just leave it for my teacher I guess.. a long wait, thanks anyways

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