document.write( "Question 245928: Anne's age is seven tenths of Bill's age. In 4 yrs Anne's age will be eight eleventh's of Bill's age. How old is Bill now? \n" ); document.write( "
Algebra.Com's Answer #179609 by richwmiller(17219)\"\" \"About 
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let a= Anne's age
\n" ); document.write( "let b= Bill's age
\n" ); document.write( "a=(7/10)*b -their ages now\r
\n" ); document.write( "\n" ); document.write( "a+4=(8/11)*(b+4) -their ages in four years
\n" ); document.write( "Substitute (7/10)*b for a in the second equation
\n" ); document.write( "(7/10)*(b)+4=(8/11)*(b+4)
\n" ); document.write( "multiply both sides by 110 (10*11)
\n" ); document.write( "77*b+440=80*(b+4)
\n" ); document.write( "77*b+440=80*b+80*4
\n" ); document.write( "77*b+440=80*b+320
\n" ); document.write( "subtract 320 from both sides
\n" ); document.write( "77b+120=80b
\n" ); document.write( "subtract 77b from both sides
\n" ); document.write( "120=3b
\n" ); document.write( "divide both sides by 3
\n" ); document.write( "40=b Bill is 40 years old
\n" ); document.write( "a=(7*40)/10
\n" ); document.write( "a=7*4=28
\n" ); document.write( "check
\n" ); document.write( "32=(8/11)*(44)
\n" ); document.write( "32=8*4=32
\n" ); document.write( "ok\r
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