How Does Poisson Distribution Estimate Flaws in a 40 Square Foot Metal Sheet?

AI Thread Summary
The discussion focuses on using the Poisson distribution to estimate the probability of flaws in a 40 square foot metal sheet, given a flaw rate of 1 per 10 square feet. The calculation involves determining the expected number of flaws (np) for the 8 x 5 feet area, which translates to 4 flaws in total. Participants clarify the formula e^-np * np^k/k! for calculating probabilities, leading to a consensus on the approach. The conversation includes some light-hearted banter about the difficulty of the problem. Ultimately, the group arrives at a solution, demonstrating the application of the Poisson distribution in this context.
semidevil
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so flaws in metal produced by high temperatures occur at a rate of 1 per 10 square feet. what is the probability that there is 3 or more flaws in a 8 x 5 feet.

ok, so I know we need to use poisson disstribution on this, e^-np * np^k/k!.

howver, I don't know my np.

so 1 per 10 square feet means 1 per 10 x 10 feet...maybe we can say this is the same as .1 per 1 x 1 feet.

so how do I put this in terms of 8 x 5 feet?
 
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8*5 = 40 square feet...
you have 1 per 10 square feet... that's means...

even a 10 years old kids can do this problem...

what grade are you in? I don't realize middle school teachers start teaching poisson equation to the 7th grader...
 
vincentchan said:
8*5 = 40 square feet...
you have 1 per 10 square feet... that's means...

even a 10 years old kids can do this problem...

what grade are you in? I don't realize middle school teachers start teaching poisson equation to the 7th grader...


haha...whoops, wasn't thinking about this...I got it...haha
 
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