document.write( "Question 149782: Please can you help me: problem: A student has earned scores of 87,81, and 88 on the first 3 of 4 tests. If the student wants an average (arithmetic mean) of exactly 87, what score must she earn on the fourth test?
\n" ); document.write( "I need a solution of how to set the equation up and steps on how to solve the problem. Can anyone help me. Thanks \n" ); document.write( "

Algebra.Com's Answer #109889 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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A student has earned scores of 87,81, and 88 on the first 3 of 4 tests. If the student wants an average (arithmetic mean) of exactly 87, what score must she earn on the fourth test?
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\n" ); document.write( "Let the 4th test score = x
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\n" ); document.write( "write an average equation which states the problem
\n" ); document.write( " $\"%28%2887+%2B+81+%2B+88+%2B+x%29%29%2F4\"$ = 87
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\n" ); document.write( "Add up the given values:
\n" ); document.write( " $\"%28%28x%2B256%29%29%2F4\"$ = 87
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\n" ); document.write( "We can get rid of the denominator by multiplying both sides by 4,
\n" ); document.write( "x + 256 = 4*87
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\n" ); document.write( "x + 256 = 348
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\n" ); document.write( "Subtract 256 from both sides
\n" ); document.write( "x = 348 - 256
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\n" ); document.write( "x = 92 is the score required in the 4th test.
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\n" ); document.write( "Check our solution on a calc enter (87 + 81 + 88 + 92)/4 = 87
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\n" ); document.write( "Did this make sense to you? \n" ); document.write( "

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