document.write( "Question 208630: A man who is 40 years old has three sons, ages 6,3,and 1 . in how many years will the combined age of his three sons equal 80% of his age ? \n" ); document.write( "

Algebra.Com's Answer #157792 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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A man who is 40 years old has three sons, ages 6,3,and 1 .
\n" ); document.write( "in how many years will the combined age of his three sons equal 80% of his age?
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\n" ); document.write( "Let x = no. of years for this to be true
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\n" ); document.write( "(x+6) + (x+3) + (x+1) = .8(x+40)
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\n" ); document.write( "3x + 10 = .8x + 32
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\n" ); document.write( "3x - .8x = 32 - 10
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\n" ); document.write( "2.2x = 22
\n" ); document.write( "x = $\"22%2F2.2\"$
\n" ); document.write( "x = 10 years
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\n" ); document.write( "See if that is true
\n" ); document.write( "16 + 13 + 11 = .8(50)
\n" ); document.write( "40 = 40 \n" ); document.write( "

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