SOLUTION: The sales Manager of an Automobile dealer estimated 80% of the new cars delivered by them have no defect and so will not be brought back immediately for repair. He sells a flee

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Question 252250: The sales Manager of an Automobile dealer estimated 80% of the new cars delivered by them have no defect and so will not be brought back immediately for repair. He sells a fleet of 10 cars to an important customer. What i» the probability that —
(i) No car will be brought back
(ii) Exactly two cars will be brought back.
(iii) At least two cars will be brought back.

b) State the laws of probability.
c) Describe giving examples different types of events.
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
Binomial expansion: (a+b)^10=a^10+10a^9b+45a^8b^2+... This is the only part of the expansion that we need.
Let a=.8, b=.2
.
No car returned: .8^10=.107
.
Exactly 2 returned: 45*.8^8*.2^2=.302
.
At least 2 returned:
10*.8^9*.2=.268 (exactly 1 returned)
1-.107-.268=.624 (1-one or none returned=at least 2 are returned.)
.
Ed