rson is paid a mont salary. The wiwysoal aspect however, what person has neveed w be easi as vowaww to chance one month shown in the vable. Each wonth a rawawom weember wierwh used in order to find out how much this eersen ot gewing any vanae wwenth w tw of three possible values e chance Riven wwonwh independent of any other value, so this person es pasd. The arvy win be paid $6,670, or ss soo, or sa 24o on can see the probability of getting any one of these valvse is not the same 6.67 o Soo Tsa 3ao Here is the mean and standard deviation tor this distravetion a. [4] What is the probability that this person, on a randomly selected month, is paid over ssooo? [4] The person works at this company for 120 months, what is the probability that 20 or more of the paychecks were he $6,670 amount? The person works at company for 120 months (10 years).. what is the probability that the average pay this e 120 months is $4100 or less?
(a) P(X>5000)=P(X=6670)+P(X=5500) =0.1+0.3=0.4
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(b)mean=n*p=120*0.1=12
standard deviation=sqrt(n*p*(1-p))=sqrt(120*0.1*0.9)=3.286335
So the probability is
P(X>=20) = P((X-mean)/s >(20-12)/3.286335)
=P(Z>2.43) =0.0075 (from standard normal table)
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(c)P(xbar<4100) = P((xbar-mean)/(s/vn) <(4100-4261)/(1290.38/sqrt(120)))
=P(Z<-1.37)
=0.0853 (from standard normal table)