Question 59209: pleae help me in this
let abowl contain 10 chips of he same size and shape , one and only one of these chips is red , continue to draw chips from the bowl , one at atime and at random without replacement , until red chip is drawn ,
1. find the pdf. Of X , the number of trials needed to draw the red chip
2. compute p(X< or equal 4 )
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! let abowl contain 10 chips of he same size and shape , one and only one of these chips is red , continue to draw chips from the bowl , one at atime and at random without replacement , until red chip is drawn ,
1. find the pdf. Of X , the number of trials needed to draw the red chip
P(1)=1/10
P(2)=(9/10)(1/9)=1/10
P(3)=(9/10)(8/9)(1/8)=1/10
...
P(10)=(9/10)(8/9)(7/8)...(1/2)(1/1)=1/10
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E(X)=(1/10)(1+2+3+...+9+10)=5.5
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2. compute p(X< or equal 4 )
=4/10
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Cheers,
Stan H.
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