document.write( "Question 719105: the sum of the ages of father and his son his is 40 years. if they both live on till the son becomes as old as father is now , the sum of thier ages will be 96 years. find thier present ages \n" ); document.write( "
Algebra.Com's Answer #441198 by stanbon(75887)\"\" \"About 
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the sum of the ages of father and his son his is 40 years. if they both live on till the son becomes as old as father is now , the sum of thier ages will be 96 years. find thier present ages
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\n" ); document.write( "Equations:
\n" ); document.write( "f + s = 40
\n" ); document.write( "Note: Father's age now is 40-s
\n" ); document.write( "Son's age will be \"as old as father is now\" = s + (40-s) = 40
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\n" ); document.write( "40 + (f + (40-s)) = 96
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\n" ); document.write( "Substitute for f and solve for \"s\":
\n" ); document.write( "40 + (40-s) + (40-s) = 96
\n" ); document.write( "120 - 2s = 96
\n" ); document.write( "2s = 24
\n" ); document.write( "s = 12 yrs (son's age now)
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\n" ); document.write( "f = 40-s = 28 yrs (father's age now)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \r
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