Posted by Anonymous on Sunday, July 22, 2012 at 11:39pm.
) 43% of adults receive phone calls during the day. Amongst 10 randomly
selected people find the probability that
a. Adults receive exactly 4 phone calls.
b. Adults receive 8 or more phone calls.

statistics  MathMate, Monday, July 23, 2012 at 9:19am
Binomial distribution:
p=0.43 (probability of success)
q=1p=0.57
N=10 (sample size)
Probability of r successes out of N:
P(X=r)=C(N,r)p^r*q^(Nr)
and C=combination=N!/(r!(Nr)!)
a. r=4
P(X=4)=C(10,4)*0.43^4*0.57^(104)=0.24
b. r≥8
P(X≥8)
=P(X=8)+P(X=9)+P(x=10)
= similar calculations as above
Answer This Question
Related Questions
 Math  On July 5th six different people reported to the police that they had ...
 Math problem soving  Ok if someone can help me understand I greatly appreciated...
 Math statistics  A mountain search and rescue team received an average of 600 ...
 Math problem soving  Ok if someone can help me understand I greatly appreciated...
 Statistics  A local fire station receives an average of 0.5 rescue calls per ...
 Statistics  A local fire station receives an average of 0.5 rescue calls per ...
 Smartphone Help  This is an assignment in which I have to list down ...
 Algebra  ABC phone company charges $18 per month plus 7 cents per minute of ...
 statistics  A sales firm receives an average of four calls per hour on its toll...
 statistics  Mary has already spent 1 minute on the phone, and she expects to ...
More Related Questions