document.write( "Question 1037987: Mariana averaged 83 on her first three history exams . The first score was 90. The second score was 3 less that then third score. What did she score on the second and third exams ? \n" ); document.write( "

Algebra.Com's Answer #652678 by Fombitz(32388) $\"\"$ $\"About$

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So the average was,
\n" ); document.write( " $\"A=%2890%2BX%2BY%29%2F3=83\"$
\n" ); document.write( "and
\n" ); document.write( " $\"X=Y-3\"$
\n" ); document.write( "Substituting,
\n" ); document.write( " $\"%2890%2BY-3%2BY%29%2F3=83\"$
\n" ); document.write( " $\"87%2B2Y=249\"$
\n" ); document.write( " $\"2Y=162\"$
\n" ); document.write( " $\"Y=81\"$
\n" ); document.write( "So then,
\n" ); document.write( " $\"X=81-3\"$
\n" ); document.write( " $\"X=78\"$
\n" ); document.write( "So her test scores are 90,78, and 81.
\n" ); document.write( " \n" ); document.write( "

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