Question 251974
The probability that a small business will go bankrupt in its first year is .21. For 50 such small businesses, find the following probabilities first by using the binomial probability formula, and then by using the normal
approximation.
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a. Exactly 8 go bankrupt.
binomial: P(x=8) = 50C8(0.21)^8*(0.79)^42 = 0.1019
normal approx: normalcdf(7.5,8.5,50*0.21,(50*0.21*0.79)^0.5) = 0.949...
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b. No more than 2 go bankrupt.
binomial: P(0<= x <=2) = binomcdf(50.0.21,2) = 0.0007674...
normal: normalcdf(49.5,50.5,50*0.21,(50*0.21*0.79)^0.5)) = 4.609x10^-42
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Cheers,
Stan H.