document.write( "Question 611077: paul is 4 years younger than his brother. in 4 years, paul will be three-fourths as old as his brother. how old are they now? \n" ); document.write( "
Algebra.Com's Answer #384782 by Maths68(1474)\"\" \"About 
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Let
\n" ); document.write( "Present age of Paul = p
\n" ); document.write( "Present age of his brother = b\r
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\n" ); document.write( "\n" ); document.write( "Paul is 4 years younger than his brother
\n" ); document.write( "p=b-4...........(1)\r
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\n" ); document.write( "\n" ); document.write( "In 4 years,
\n" ); document.write( "Paul will be = p+4
\n" ); document.write( "His brother be = b+4
\n" ); document.write( "Then
\n" ); document.write( "Paul will be three-fourth as old as his brother
\n" ); document.write( "p+4=3/4(b+4)
\n" ); document.write( "4(p+4)=3(b+4)
\n" ); document.write( "4p+16=3b+12
\n" ); document.write( "4p-3b=12-16
\n" ); document.write( "4p-3b=-4
\n" ); document.write( "Put the value of p from (1) to above equation
\n" ); document.write( "4(b-4)-3b=-4
\n" ); document.write( "4b-16-3b=-4
\n" ); document.write( "4b-3b=-4+16
\n" ); document.write( "b=12
\n" ); document.write( "Put the value of b in (1)
\n" ); document.write( "p=b-4
\n" ); document.write( "p=12-4
\n" ); document.write( "p=8\r
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\n" ); document.write( "\n" ); document.write( "Present age of Paul = p = 8
\n" ); document.write( "Present age of his brother = b = 12
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