document.write( "Question 1128829: The sum of David's and Jim's ages is now 65. When David is as old as Jim is now, twice Jim's age minus David's age at that time will be 110. How old is David now? \n" ); document.write( "
Algebra.Com's Answer #745351 by ankor@dixie-net.com(22740)\"\" \"About 
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The sum of David's and Jim's ages is now 65.
\n" ); document.write( " d + j = 65
\n" ); document.write( " let x = j-d (the difference in their ages)
\n" ); document.write( " When David is as old as Jim is now, twice Jim's age minus David's age at that time will be 110.
\n" ); document.write( " 2(j+x) - (d+x)) = 110
\n" ); document.write( "2j + 2x - d - x = 110
\n" ); document.write( "2j - d + x = 110
\n" ); document.write( "replace x with (j-d)
\n" ); document.write( "2j - d +(j-d) = 110
\n" ); document.write( "3j-2d = 110
\n" ); document.write( "Use elimination, multiply the 1st equation by 2
\n" ); document.write( "3j - 2d = 110
\n" ); document.write( "2j + 2d = 130
\n" ); document.write( "-----------------addition eliminates d, find j
\n" ); document.write( "5j = 240
\n" ); document.write( "j = 240/5
\n" ); document.write( "j = 48 yrs is Jim's present age
\n" ); document.write( "then
\n" ); document.write( "48 + d = 65
\n" ); document.write( "d = 65 - 48
\n" ); document.write( "d = 17 is David's age
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\n" ); document.write( "Check this in the statement
\n" ); document.write( "48 - 17 = 31 is the difference in their ages
\n" ); document.write( "2(48+31) - (17+31) = 110
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