document.write( "Question 357303: A shipment of pins contains 25 good ones and 2 defective ones. At the receiving
\n" ); document.write( "department an inspector picks three pins at random and tests them. If any
\n" ); document.write( "defective pin is found among the three that are tested, the shipment would be
\n" ); document.write( "rejected. What is the probability that the shipment would be accepted ? To
\n" ); document.write( "increase the probability of acceptance to atleast 90%, it is decided to do one of the
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\n" ); document.write( "\n" ); document.write( "1. Add some good pins to the shipment
\n" ); document.write( "2. Remove some defective pins in the shipment
\n" ); document.write( "For each of the two options, find out exactly how many pins should be added or
\n" ); document.write( "removed.
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Algebra.Com's Answer #255169 by edjones(8007)\"\" \"About 
You can put this solution on YOUR website!
(23/25)^3=.7787 probability that the shipment would be accepted.
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\n" ); document.write( "1.
\n" ); document.write( "Let x = number of pins to be added to increase the probability of acceptance to atleast 90%.
\n" ); document.write( "((23+x)/(25+x))^3>=.9
\n" ); document.write( "((23+x)/(25+x))>=.9655... Cube root of each side.
\n" ); document.write( "23+x>=.9655(25+x)
\n" ); document.write( "23+x>=24.137+.9655x
\n" ); document.write( ".0345x=1.137
\n" ); document.write( "x>=33 pins should be added.
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\n" ); document.write( "2.
\n" ); document.write( "(23/24)^3=.88 one defective pin removed.
\n" ); document.write( "Both defective pins would have to be removed to increase the probability of acceptance to atleast 90%.
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