document.write( "Question 856590: A Professor estimates the probability that he will receive at least one telephone call at home
\n" ); document.write( "during the hours of 5pm to 7pm on a weekday to be 2/3. Use the formulas for computing
\n" ); document.write( "binomial probabilities to answer the following questions:
\n" ); document.write( "(a) What is the probability that he will receive at least one call on all five of
\n" ); document.write( "the next five weekday nights?
\n" ); document.write( "(b) What is the probability that he will not receive a call on any of the next
\n" ); document.write( "five weekday nights?
\n" ); document.write( "(c) What is the probability that he will receive a call on at least four of the next
\n" ); document.write( "five weekday nights? \n" ); document.write( "

Algebra.Com's Answer #516072 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi,
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document.write( " p =2/3, n = 5
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document.write( "a) P(at least one call = 1 - P(no calls) = 1 - (1/3)^5 = .9959
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document.write( "b) P(no calls) = (1/3)^5 = .0041
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document.write( "c) P(call at least 4 days) = P(x ≥ 4) = 1 – P(x ≤ 3) = 1- normalcdf(5,2/3, 3)
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document.write( "or
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document.write( "Using:  
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document.write( "P(x ≥ 4) = P(4) + P(5) =  = .461
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