document.write( "Question 504603: shane is twice as old as his daughter in 42 years the ratio of thir ages will be 4:3 what is the daughter's current age? \n" ); document.write( "
Algebra.Com's Answer #339654 by Maths68(1474)\"\" \"About 
You can put this solution on YOUR website!
Let
\n" ); document.write( "Present age of Shane = s
\n" ); document.write( "Present age of his daughter = d\r
\n" ); document.write( "\n" ); document.write( "Given
\n" ); document.write( "Shane is twice as old as his daughter
\n" ); document.write( "s=2d ............(1)
\n" ); document.write( "In 42 years means we have add 42 in the present ages of both
\n" ); document.write( "s+42=d+42
\n" ); document.write( "then
\n" ); document.write( "ratio of thir ages will be 4:3
\n" ); document.write( "4:3=s+42:d+42
\n" ); document.write( "4/3=s+42/d+42
\n" ); document.write( "4*(d+42)=3*(s+42)
\n" ); document.write( "4d+168=3s+126
\n" ); document.write( "4d=3s+126-168
\n" ); document.write( "4d=3s+126-168
\n" ); document.write( "4d=3s-42 .............(2)
\n" ); document.write( "Put the value of s from (1) to (2)
\n" ); document.write( "4d=3(2d)-42
\n" ); document.write( "4d=6d-42
\n" ); document.write( "4d-6d=-42
\n" ); document.write( "-2d=-42
\n" ); document.write( "Divide by -2 both sides of above equation
\n" ); document.write( "-2d/-2=-42/-2
\n" ); document.write( "d=21
\n" ); document.write( "Put the value of d in (1)
\n" ); document.write( "s=2d
\n" ); document.write( "s=2(21)
\n" ); document.write( "s=42\r
\n" ); document.write( "\n" ); document.write( "Shane is 42 and her daughter is 21 years old\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "
\n" );