document.write( "Question 518687: Sarah and her sister were born 12 years apart. If sarah is 3 times older than her sister, how old are the girls? \n" ); document.write( "

Algebra.Com's Answer #345294 by Maths68(1474) $\"\"$ $\"About$

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Let
\n" ); document.write( "Present age of Sarah = s
\n" ); document.write( "Present age of sister = t
\n" ); document.write( "Sarah and her sister were born 12 years apart.
\n" ); document.write( "s-t=12
\n" ); document.write( "s=12+t.........(1)
\n" ); document.write( "sarah is 3 times older than her sister
\n" ); document.write( "s=3t...........(2)
\n" ); document.write( "Put the above value of s in (1)
\n" ); document.write( "3t=12+t
\n" ); document.write( "3t-t=12
\n" ); document.write( "2t=12
\n" ); document.write( "2t/2=12/2
\n" ); document.write( "t=6
\n" ); document.write( "Put the value of t in (2)
\n" ); document.write( "s=3t
\n" ); document.write( "s=3*6
\n" ); document.write( "s=18
\n" ); document.write( "Present age of Sarah = s = 18 years old
\n" ); document.write( "Present age of sister = t = 6 years old
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