document.write( "Question 313356: A father is 4 times his son’s age and in 30 years, son’s age will be half of his father’s age. How old are they now? \n" ); document.write( "
Algebra.Com's Answer #224153 by ankor@dixie-net.com(22740)\"\" \"About 
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A father is 4 times his son’s age and in 30 years, son’s age will be half of his father’s age.
\n" ); document.write( " How old are they now.
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\n" ); document.write( "Write an equation for each statement:
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\n" ); document.write( "\"A father is 4 times his son’s age\"
\n" ); document.write( "f = 4s
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\n" ); document.write( "\"and in 30 years, son’s age will be half of his father’s age.\"
\n" ); document.write( "s + 30 = .5(f + 30)
\n" ); document.write( "s + 30 = .5f + 15
\n" ); document.write( "s = .5f + 15 - 30
\n" ); document.write( "s = .5f - 15
\n" ); document.write( "Replace f with 4s
\n" ); document.write( "s = .5(4s) - 15
\n" ); document.write( "s = 2s - 15
\n" ); document.write( "15 = 2s - s
\n" ); document.write( "15 = s
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\n" ); document.write( " How old are they now?
\n" ); document.write( "son = 15 yrs, father: 4(15) = 60 yrs
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\n" ); document.write( "Check solution in the statement:
\n" ); document.write( "\"in 30 years, son’s age will be half of his father’s age.\"
\n" ); document.write( "15 + 30 .5(60 + 30)
\n" ); document.write( "45 = .5(90) \n" ); document.write( "
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