document.write( "Question 499621: doug dave and don are counting ducks down by the pond they are havinf a contest to see who can spot the most ducks. doug counts twice as many as dave. dave counts twice as many as don. together they spotted a total of 42 ducks. how many ducks did each boy spot \n" ); document.write( "
Algebra.Com's Answer #337809 by Earlsdon(6294)\"\" \"About 
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Let a = Doug's count of ducks, b = Dave's count, and c = Don's count.
\n" ); document.write( "a = 2b \"Doug counts twice as many as Dave.\"
\n" ); document.write( "b = 2c \"Dave counts twice as many as Don.\"
\n" ); document.write( "a+b+c = 42 \"\"Together they spotted a total of 42 ducks.\"
\n" ); document.write( "Rewrite the first equation:
\n" ); document.write( "a = 2b Replace b = 2c to get:
\n" ); document.write( "a = 2(2c)
\n" ); document.write( "a = 4c Now rewrite the second equation:
\n" ); document.write( "a+b+c = 42 Substitute a = 4c and b = 2c.
\n" ); document.write( "4c+2c+c = 42 Simplify.
\n" ); document.write( "7c = 42 Divide by 7.
\n" ); document.write( "c = 6 and...
\n" ); document.write( "b = 2(6)
\n" ); document.write( "b = 12 and...
\n" ); document.write( "a = 4c
\n" ); document.write( "a = 4(6)
\n" ); document.write( "a = 24.
\n" ); document.write( "Doug spotted 24 ducks.
\n" ); document.write( "Dave spotted 12 ducks.
\n" ); document.write( "Don spotted 6 ducks. \n" ); document.write( "
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