document.write( "Question 505061: bani is 5 years older than his sister. In 3 years he will be twice as old as she is. How old is bani? \n" ); document.write( "
Algebra.Com's Answer #339862 by Maths68(1474)\"\" \"About 
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Let
\n" ); document.write( "Present age of Bani = b
\n" ); document.write( "Present age of sister = s
\n" ); document.write( "Bani is 5 years older than his sister means if we add 5 to sister's age both ages will be same
\n" ); document.write( "b=s+5...........(1)
\n" ); document.write( "In 3 years means we have to add 3 in their present ages
\n" ); document.write( "b+3=s+3
\n" ); document.write( "then
\n" ); document.write( "he will be twice as old as she is
\n" ); document.write( "b+3=2(s+3)
\n" ); document.write( "b+3=2s+6
\n" ); document.write( "b=2s+6-3
\n" ); document.write( "b=2s+3
\n" ); document.write( "Put the value of b from (1) to above eqution
\n" ); document.write( "s+5=2s+3
\n" ); document.write( "s=2s+3-5
\n" ); document.write( "s-2s=-2
\n" ); document.write( "-s=-2
\n" ); document.write( "Multiply by (-1) both sides of the equation
\n" ); document.write( "(1)(-s)=(-1)(-2)
\n" ); document.write( "s=2
\n" ); document.write( "Put the value of s in (1)
\n" ); document.write( "b=s+5...........(1)
\n" ); document.write( "b=2+5
\n" ); document.write( "b=7\r
\n" ); document.write( "\n" ); document.write( "Present age of Bani = b = 7
\n" ); document.write( "Present age of sister = s = 2
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