document.write( "Question 1142730: In the following problem, check that it is appropriate to use the normal approximation to the binomial. Then use the normal distribution to estimate the requested probabilities. \r
\n" ); document.write( "\n" ); document.write( "It is known that 83% of all new products introduced in grocery stores fail (are taken off the market) within 2 years. If a grocery store chain introduces 62 new products, find the following probabilities. (Round your answers to four decimal places.)
\n" ); document.write( "(a) within 2 years 47 or more fail
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\n" ); document.write( "\n" ); document.write( "(b) within 2 years 58 or fewer fail
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\n" ); document.write( "\n" ); document.write( "(c) within 2 years 15 or more succeed
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\n" ); document.write( "\n" ); document.write( "(d) within 2 years fewer than 10 succeed
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Algebra.Com's Answer #763800 by Boreal(15235)\"\" \"About 
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mean is np=62*0.83=51.46
\n" ); document.write( "variance is np(1-p)=51.46*0.17=8.7482
\n" ); document.write( "sd is sqrt (V)=2.96
\n" ); document.write( "47 or more use 46.5 as continuity correction factor
\n" ); document.write( "z>(46.5-51.46)/2.96=-1.68
\n" ); document.write( "0.9535\r
\n" ); document.write( "\n" ); document.write( "58 or fewer use 58.5
\n" ); document.write( "(58.5-51.46)/2.96 or z<2.38 with probability of 0.9913\r
\n" ); document.write( "\n" ); document.write( "15 or more succeed is 47 or fewer fail
\n" ); document.write( "z< (47-51.46)/2.96=-1.51
\n" ); document.write( "that has probability of 0.0655\r
\n" ); document.write( "\n" ); document.write( "fewer than 10 succeed means no more than 9 do which means that at least 53 fail.
\n" ); document.write( "z>(53-51.46)/2.96 or z>0.52 0.3015 probability.\r
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