SOLUTION: It is reported that 77% of workers aged 16 and over drive to work alone. Choose 8 workers at random. Find the probability that a. All drive to work alone b. More than one hal

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Question 1167603: It is reported that 77% of workers aged 16 and over drive to work alone. Choose 8 workers at random. Find the probability that
a. All drive to work alone
b. More than one half drive to work alone
c. Exactly 3 drive to work alone

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
a. This is .77^8=0.1236
c. exactly 3 is 8C3*.77^3*.23^5=0.0165
b. look at 0,1,2, and 3 and subtract that sum from 1.
have 3
for 1 it is 8*0.77*0.23^7=0.0002
for 0 it is <0.0001 (.23^8)
for 2 it is 28*0.77^2*0.23^6=0.0024
for 4 it is 70*0.77^4*0.23^4=0.0689
for <=4 it is probability 0.0880, so the answer is the complement or 0.9120