document.write( "Question 1197318: a)A quality control engineer inspects a random sample of three batteries from a lot of 30 car batteries, which are ready to be shipped. If such a lot contains ten batteries with slight defects,\r
\n" ); document.write( "\n" ); document.write( "what then is the probability that the inspector's sample contain
\n" ); document.write( " i. none of the batteries with slight defects?
\n" ); document.write( " i i. at least one of the batteries with slight defects? \r
\n" ); document.write( "\n" ); document.write( "B)The probability that a bomber hits its target on any particular run is 80%. If three bombers sent out after the same target, what then is the probability that at least one of the three bombers will hit the target? [Marks -5] \n" ); document.write( "

Algebra.Com's Answer #830577 by ikleyn(52832) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "a) A quality control engineer inspects a random sample of three batteries from a lot
\n" ); document.write( "of 30 car batteries, which are ready to be shipped. If such a lot contains ten batteries
\n" ); document.write( "with slight defects, what then is the probability that the inspector's sample contain
\n" ); document.write( "i. none of the batteries with slight defects?
\n" ); document.write( "ii. at least one of the batteries with slight defects?
\n" ); document.write( "b) The probability that a bomber hits its target on any particular run is 80%.
\n" ); document.write( "If three bombers sent out after the same target, what then is the probability
\n" ); document.write( "that at least one of the three bombers will hit the target? [Marks -5]
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\n" ); document.write( "\n" ); document.write( "            The solution by @ewatrrr for the first problem (a) is WRONG for both (i) and (ii)
\n" ); document.write( "            not only numerically, but CONCEPTUALLY.\r
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\n" ); document.write( "\n" ); document.write( "            This problem IS NOT on binomial distribution.\r
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\n" ); document.write( "\n" ); document.write( "            I came to bring you a correct solution.\r
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document.write( "(i) The probability in this problem is the ratio of two numbers.\r\n" );
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document.write( "    The denominator is the number of all possible triples of batteries from \r\n" );
document.write( "    the whole set of 30 batteries.  The number of such triples is the number of all combinations\r\n" );
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document.write( "         =  = 4060.\r\n" );
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document.write( "    The numerator of this fraction is the number of all triples comprising of good batteries.\r\n" );
document.write( "    It is the number of combinations   =  =  = 1140.\r\n" );
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document.write( "    Thus the probability  P(i) =  =  =  = 0.2808  (rounded).    ANSWER\r\n" );
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document.write( "(ii)  In this problem, the probability is the COMPLEMENT to what we found in (i)\r\n" );
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document.write( "         P(ii) = 1 - P(i) = 1 - 0.2808 = 0.7192   (rounded).    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Next problem was solved several times by different tutors today, so I do not touch it.\r
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\n" ); document.write( "\n" ); document.write( "In the future, please do not post more than one problem per post.\r
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\n" ); document.write( "\n" ); document.write( "It is the REQUIREMENT, the RULE and the POLICY of this forum.\r
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\n" ); document.write( "\n" ); document.write( "Do not make this stupid mistake.\r
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