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Just part (a), I think my answer key is wrong.
In the manufacture of glass panels, small bubbles occur at random at an average of 1 bubble in every glass panel. The number of bubbles detected in a panel is denoted by X and follows a Poisson distribution.
(a) find the probability that, in a randomly chosen glass panel, there are at least three bubbles. [ans=0.0144?]
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Nope, cos i am a FM student last time... speed in calculation meant something to us.
Ok enough of talking, i teach u a simple method.
for P(x=0) + P(x=1) + P(x=2), type e^(-1) [ 1+1+1/2] in your calculator
In general, P(x=0) + P(x=1) + P(x=2) + .... = e^(-y) [ 1 + y + y^2/2 + ....] , y = lumda
anyway, ur calcuator cannot calculate P(X<=2) directly.
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Originally posted by secretliker:
My calculator can calculate P(X<=2). Maybe last time cannot.
You're using the formula for Poisson distribution right?
( e^-y ) [ (y^x) / x! ] , where y=lambda.
It's in the formulae booklet but I seldom use it cos now everything is simplified by the GC.
haha secretliker.Let me share with u what i told my math student and what me and eagle share in common about the use of calculator.
I strongly discouraged u from relying on calculator as....
1) u will miss out a lot of concept when u rely on it. a classical example is the sketching of graph.... which involves differentiation, partial fraction and finding the intercepts.....
2) what if ur calculator spoil and cannot be replaced? U have to re-learn all the functions (worst still some functions got several symbols and wordings).
Therefore, i urge u to use calculator for PLAIN calculation and not relying on it to solve question (but for double checking is fine).
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