document.write( "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 —
\n" ); document.write( "(i) No car will be brought back
\n" ); document.write( "(ii) Exactly two cars will be brought back.
\n" ); document.write( "(iii) At least two cars will be brought back.\r
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\n" ); document.write( " b) State the laws of probability.
\n" ); document.write( " c) Describe giving examples different types of events. \n" ); document.write( "

Algebra.Com's Answer #184069 by edjones(8007) $\"\"$ $\"About$

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.
\n" ); document.write( "Let a=.8, b=.2
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\n" ); document.write( "No car returned: .8^10=.107
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\n" ); document.write( "Exactly 2 returned: 45*.8^8*.2^2=.302
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\n" ); document.write( "At least 2 returned:
\n" ); document.write( "10*.8^9*.2=.268 (exactly 1 returned)
\n" ); document.write( "1-.107-.268=.624 (1-one or none returned=at least 2 are returned.)
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\n" ); document.write( "Ed \n" ); document.write( "

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