document.write( "Question 826864: the average of a class of 22 students is 21 years. the average increases by 1 when the teachers age is also included. what is the age of the teacher?
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Algebra.Com's Answer #498295 by Alpha Maximus(4) $\"\"$ $\"About$

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The definition of an average is the ratio of the sum of a number of values to the number of values. Since we don't have the sum, let it be 'x'
\n" ); document.write( "But we do have the number of values which is 22. Thus,
\n" ); document.write( "X/22=21, x=22*21= 462. The previously unknown sum is 462. We're now told that the average undergoes a unit increment (21+1=22), when the teachers age is added to the sum. Let the teacher's age be 'y'. Note that the number of values also increases by one(I.e: 22+1=23). Thus we have:
\n" ); document.write( "462+y/22=23, 462+y=506, y=506-462,y=44
\n" ); document.write( "Thus,it has been established that the teacher is 44yrs old. \n" ); document.write( "

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