Question 247286
A burglar alarm system has six fail-safe components. The probability of each failing in 0.05. Find the following probabilities. 
a. Exactly three will fail
P(x=3) = 6C3*(0.05)^3(0.95)^3 = 0.0021
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b. Fewer than 2 will fail
I use a calculator for these:
P(0<= x <= 1) = binomcdf(6,0.05,1) = 0.9672...
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c. None will fail
P(x=0) = 0.95^6 = 0.7351...
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d. All will fail
P(x=6) = 0.05^6 = 0.0000000156...
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Cheers,
Stan H.