document.write( "Question 750687: At present, Gilbert's age is 30% of his father's age. Thirty years from now, Gilbert's age will be 60% of his father's age. How old is Gilbert now? \n" ); document.write( "
Algebra.Com's Answer #456925 by ankor@dixie-net.com(22740)\"\" \"About 
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At present, Gilbert's age is 30% of his father's age.
\n" ); document.write( "g = .3f (using the decimal equiv of percent)
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\n" ); document.write( " Thirty years from now, Gilbert's age will be 60% of his father's age.
\n" ); document.write( "g + 30 = .6(f+30)
\n" ); document.write( "g + 30 = .6f + 18
\n" ); document.write( "g = .6f = 18 - 30
\n" ); document.write( "g = .6f - 12
\n" ); document.write( "Replace g with .3f
\n" ); document.write( ".3f = .6f - 12
\n" ); document.write( "12 = .6f - .3f
\n" ); document.write( "12 = .3f
\n" ); document.write( "f = 12/.3
\n" ); document.write( "f = 40 yrs is Dad's age
\n" ); document.write( " How old is Gilbert now?
\n" ); document.write( "g = .3(40)
\n" ); document.write( "g = 12 yrs
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\n" ); document.write( "Check this
\n" ); document.write( "12 + 30 = .6(40+30)
\n" ); document.write( "42 = .6(70)
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