document.write( "Question 498115: Janis is 3 years older than her sister. Thirty years from now the sum of their ages will be 111. Find the current ages of the sisters. \n" ); document.write( "
Algebra.Com's Answer #338052 by Maths68(1474)\"\" \"About 
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Let
\n" ); document.write( "Present age of Janis = j
\n" ); document.write( "Present age of sister = s\r
\n" ); document.write( "\n" ); document.write( "Janis is 3 years older means if we add 3 to the sister age both girls will be of same age
\n" ); document.write( "j=s+3 ............(1)
\n" ); document.write( "Thirty years from now means we have to add 30 in their present ages then sum them up
\n" ); document.write( "(j+30)+(s+30)=111
\n" ); document.write( "j+30+s+30=111
\n" ); document.write( "j+s+60=111
\n" ); document.write( "j+s=111-60
\n" ); document.write( "j+s=51 ...........(2)
\n" ); document.write( "Plug in the value of j from (1) to (2)
\n" ); document.write( "(s+3)+s=51
\n" ); document.write( "s+3+s=51
\n" ); document.write( "2s+3=51
\n" ); document.write( "2s=51-3
\n" ); document.write( "2s=48
\n" ); document.write( "Divide by 2 both sides of the equation
\n" ); document.write( "2s/2=48/2
\n" ); document.write( "s=24
\n" ); document.write( "Plug in the value of s in (1)
\n" ); document.write( "j=s+3
\n" ); document.write( "j=24+3
\n" ); document.write( "j=27
\n" ); document.write( "Present age of Janis = 27
\n" ); document.write( "Present age of sister = 24\r
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