document.write( "Question 75466: Q1. A final exam in math 160 has a mean of 73 with standard deviation 7.8. If 24 students are randomly selected, find the probability that the mean of their test score is greater than 78.\r
\n" ); document.write( "\n" ); document.write( "Q2.For the binomial distribution with the given values for n and p, state whether or not it is suitable to use the normal distribution as an approximation. n = 16 and p = 0.5\r
\n" ); document.write( "\n" ); document.write( "Q3. This is the same as question 1, but find the probability that the mean of their test scores is LESS than 70\r
\n" ); document.write( "\n" ); document.write( "Q4. Estimate the indicated probability by using the normal distribution as an approximation to the binomial distribution. With n = 20 and p = 0.06, estimate p (fewer than 8).
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Algebra.Com's Answer #54160 by stanbon(75887)\"\" \"About 
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Q1. A final exam in math 160 has a mean of 73 with standard deviation 7.8. If 24 students are randomly selected, find the probability that the mean of their test score is greater than 78.
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\n" ); document.write( "z(78)=(78-73)/7.8/sqrt(24)=3.14
\n" ); document.write( "P(z>3.14)=0.0008448059....
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\n" ); document.write( "Q2.For the binomial distribution with the given values for n and p, state whether or not it is suitable to use the normal distribution as an approximation. n = 16 and p = 0.5
\n" ); document.write( "The answer to this depends on the conditions listed in your text for using
\n" ); document.write( "a normal approximation on a binomial problem.
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\n" ); document.write( "\n" ); document.write( "Q3. This is the same as question 1, but find the probability that the mean of their test scores is LESS than 70
\n" ); document.write( "z(70)=(70-73)/7.8/sqrt(24)=-1.88442228...
\n" ); document.write( "P(z<-1.88442228...)=0.02975...
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\n" ); document.write( "Q4. Estimate the indicated probability by using the normal distribution as an approximation to the binomial distribution. With n = 20 and p = 0.06, estimate
\n" ); document.write( "P(fewer than 8).
\n" ); document.write( "Z(8)=(8-20*0.06)/sqrt(20*0.06*0.94)=6.8/1.06207=6.40257
\n" ); document.write( "P(z<6.40257)=0.9999
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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