document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1147269>Question 1147269</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the average age of four sisters is 24. The average age of eldest three is 26, how old is the youngest sister? </SPAN>\n" );
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document.write( "If an algebraic solution is not required, this can be solved informally using the fact that all the ages are \"close together\".<br><BR>\n" );
document.write( "The average age of all four is 24; the average age of the three oldest is 26.  On average, then, the age of each of the three oldest is 2 years above the average.<br><BR>\n" );
document.write( "So all together, the ages of those three is 3*2=6 over the average.  That means the age of the youngest has to be 6 years under the average.<br><BR>\n" );
document.write( "ANSWER: 24-6 = 18 </SPAN>\n" );
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