document.write( "Question 770242: Two mathematics classes in Year 12 general maths course sat for some assessment task and some results are shown below:\r
\n" ); document.write( "\n" ); document.write( "Class 1: Number of students=25 and average mark is 52%
\n" ); document.write( "Class2: Number of students=20 and average mark is 70%\r
\n" ); document.write( "\n" ); document.write( "What is average mark for the course?\r
\n" ); document.write( "\n" ); document.write( "PS. I calculated the answer to be 61 but apparently that is incorrect. This was shown by:
\n" ); document.write( "52 plus 70 divided by 2 \n" ); document.write( "

Algebra.Com's Answer #469387 by ramkikk66(644) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "Class 1: Number of students=25 and average mark is 52%\r\n" );
document.write( "Class2: Number of students=20 and average mark is 70% \r\n" );
document.write( "What is average mark for the course? \r\n" );
document.write( "Ans:\r\n" );
document.write( "You cannot just take the overall average as 52 plus 70 divided by 2, because\r\n" );
document.write( "the number of students in each class is different.\r\n" );
document.write( "Average = total number of marks / number of students.\r\n" );
document.write( "Therefore total marks = Number of students * average.\r\n" );
document.write( "Class1: Average = 52, students = 25, so total = 52*25 = 1300\r\n" );
document.write( "Class2: Average = 70, students = 20, so total = 70*20 = 1400\r\n" );
document.write( "Overall average for the course = Total marks of both the classes / total students \r\n" );
document.write( "of both the classes\r\n" );
document.write( "= \r\n" );
document.write( "Hope you got it :)\r\n" );
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