document.write( "Question 1194419: Which of the following exam grades has a better relative position?
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document.write( "a.) A grade of 43 on a algebra test with x̄=40 and s=3
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document.write( "b.) A grade of 75 on a geometry test with x̄=72 and s=5\r
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document.write( "Show full solution, thank you! \n" );
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Algebra.Com's Answer #826618 by math_tutor2020(3816)![]() ![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "The z score formula is \n" ); document.write( "z = (x - mu)/sigma \n" ); document.write( "where, \n" ); document.write( "x = raw score \n" ); document.write( "mu = mean \n" ); document.write( "sigma = standard deviation\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "I'll treat each xbar as mu, and each s as sigma\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "For part A, we have \n" ); document.write( "x = 43 \n" ); document.write( "mu = 40 \n" ); document.write( "sigma = 3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So, \n" ); document.write( "z = (x - mu)/sigma \n" ); document.write( "z = (43-40)/3 \n" ); document.write( "z = 3/3 \n" ); document.write( "z = 1 \n" ); document.write( "which is the z score to part A.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "A z score of 1 means we're exactly 1 standard deviation above the mean. \n" ); document.write( "Positive z scores are above the mean, while negative z scores are below the mean.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "For part B, we have this z score \n" ); document.write( "z = (x - mu)/sigma \n" ); document.write( "z = (75 - 72)/5 \n" ); document.write( "z = 3/5 \n" ); document.write( "z = 0.6\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "We can see that the z score in part A is larger; therefore, the exam grade in class A is in a better relative position to the entire class.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Answer: Choice A. \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " |