document.write( "Question 1052885: The average mark on a test for a class of 35 students was 61%. The average mark obtained by the 15 girls in the class was 65%. What was the average mark obtained by the boys? \n" ); document.write( "
Algebra.Com's Answer #668175 by josmiceli(19441)\"\" \"About 
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[ ave mark ] = [ total of marks ] / [ number of students ]
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\n" ); document.write( "For all the students:
\n" ); document.write( "\"++61+=+T+%2F+35+\"
\n" ); document.write( "\"+T+=+2135+\"
\n" ); document.write( "Total of marks for all students
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\n" ); document.write( "For the girls:
\n" ); document.write( "\"+65+=+T%2F15+\"
\n" ); document.write( "\"+T+=+975+\"
\n" ); document.write( "Total of marks for girls
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\n" ); document.write( "\"+2135+-+975+=+1160+\"
\n" ); document.write( "and
\n" ); document.write( "\"+35+-+15+=+20+\"
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\n" ); document.write( "Let \"+x+\" = the average mark for the boys
\n" ); document.write( "\"+x+=+1160%2F20+\"
\n" ); document.write( "\"+x+=+58+\"
\n" ); document.write( "The average mark for the boys is 58
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