document.write( "Question 1018967: I really need your help in solving this problem. I appreciate your time and efforts. Have a terrific day :) Here is the question:\r
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document.write( "In a population of exam scores, a score of X=48 corresponds to Z= +1.00 and a score of X = 36 corresponds to Z = - 0.50. Find the mean and standard deviation for the population. \n" );
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Algebra.Com's Answer #634972 by mathmate(429)![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "Question: \n" ); document.write( "In a population of exam scores, a score of X=48 corresponds to Z= +1.00 and a score of X = 36 corresponds to Z = - 0.50. Find the mean and standard deviation for the population. \n" ); document.write( " \n" ); document.write( "Solution: \n" ); document.write( "Using Z=(X-μ)/σ, \n" ); document.write( "we substitute into the given data: \n" ); document.write( "1.0=(48-μ)/σ \n" ); document.write( "=> \n" ); document.write( "μ+σ=48........(1) \n" ); document.write( "-0.50=(36-μ)/σ \n" ); document.write( "=> \n" ); document.write( "μ-0.5σ=36 .....(2) \n" ); document.write( " \n" ); document.write( "(1)-(2) \n" ); document.write( "1.5σ=12 =>σ=8.....(3) \n" ); document.write( " \n" ); document.write( "Substitute (3) in (1) \n" ); document.write( "μ+8=48 => μ=40 ......(4) \n" ); document.write( " \n" ); document.write( "Check: \n" ); document.write( "(48-40)/8=1 \n" ); document.write( "(36-40)/8=-0.5 \n" ); document.write( "so both are correct. \n" ); document.write( " |