document.write( "Question 1021544: susan is 4/5 as old as Ronald. four years ago, she was 3/4 as old as ronald. how old each? \n" ); document.write( "

Algebra.Com's Answer #637290 by josmiceli(19441) $\"\"$ $\"About$

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(1) $\"+s+=+%284%2F5%29%2Ar+\"$
\n" ); document.write( "(2) $\"+s+-+4+=+%283%2F4%29%2A%28+r+-+4+%29+\"$
\n" ); document.write( "---------------------------
\n" ); document.write( "Substitute (1) into (2)
\n" ); document.write( "(2) $\"+%284%2F5%29%2Ar+-+4+=+%283%2F4%29%2A%28+r+-+4+%29+\"$
\n" ); document.write( "Multiply both sides by $\"+20+\"$
\n" ); document.write( "(2) $\"+16r+-+80+=+15%2A%28+r+-+4+%29+\"$
\n" ); document.write( "(2) $\"+16r+-+80+=+15r+-+60+\"$
\n" ); document.write( "(2) $\"+r+=+20+\"$
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+s+=+%284%2F5%29%2Ar+\"$
\n" ); document.write( "(1) $\"+s+=+%284%2F5%29%2A20+\"$
\n" ); document.write( "(1) $\"+s+=+16+\"$
\n" ); document.write( "Susan is 16 and Ronald is 20
\n" ); document.write( "-------------------------
\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+s+-+4+=+%283%2F4%29%2A%28+r+-+4+%29+\"$
\n" ); document.write( "(2) $\"16+-+4+=+%283%2F4%29%2A%28+20+-+4+%29+\"$
\n" ); document.write( "(2) $\"+12+=+%283%2F4%29%2A16+\"$
\n" ); document.write( "(2) $\"+48+=+48+\"$
\n" ); document.write( "OK\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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