Question 130945This question is from textbook Statistics
: Find these probabilties for a sample of 20 teenagers is 70% of them had compact disk players by the age of 16.
a. At least 14 had CD players
b. Excatly 9 had CD players
c. More than 17 had CD players
I think i know how to do b. but a and c i dont know how
This question is from textbook Statistics
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Find these probabilties for a sample of 20 teenagers is 70% of them had compact disk players by the age of 16.
a. P(At least 14 had CD players) = 1 - binomcdf(20,0.7,13)=0.608
b. P(Exactly 9 had CD players) = 20C9(0.7)^9*0.3^11 or binompdf(20,0.7,9)=0.012
c. P(More than 17 had CD players) = 1 - binomcdf(20,0.7,17) = 0.03548...
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Cheers,
Stan H.
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