Question 809602
Past date indicate that the probability of all repairs being completed on teh same day is actually 0.7..

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I am sure they wanted you to consider the repairs were independent.h n
Binomial with n = 5 and p(done) = 0.7 and p(not done) = 0.3
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For the first five problems reported on a given day, what is the probability that :
a) All five will be repaired on the same day?
P(x = 5) = 0.7^5 = 0.1681
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b) At least three will be repaired on the same day
P(3<= x <= 5) = 1 - binomcdf(5,0.7,2) = 0.8369 
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c) fewer than two will be repaired on the same day?
P(0>= x >=1) = binomcdf(5,0.7,1) = 0.0308 

Cheers,
Stan H.
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