document.write( "Question 156173: Bobby has a bag containing two sizes of marbles. The big ones weigh 8 g and the small ones weigh 2 g. If there are twice as many small ones as big ones and the bag weighs 324 g, how many big marbles does he have? \n" ); document.write( "
Algebra.Com's Answer #115054 by ankor@dixie-net.com(22740)\"\" \"About 
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The big ones weigh 8 g and the small ones weigh 2 g. If there are twice as many small ones as big ones and the bag weighs 324 g, how many big marbles does he have?
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\n" ); document.write( "Let x = no. of big ones
\n" ); document.write( "and
\n" ); document.write( "Let y = no. of small ones
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\n" ); document.write( "Write an equation for the total weight
\n" ); document.write( "8x + 2y = 324
\n" ); document.write( ":
\n" ); document.write( "Write an equation for the statement:
\n" ); document.write( "\"there are twice as many small ones as big ones\"
\n" ); document.write( "y = 2x
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\n" ); document.write( "Substitute 2x for y in the total weight equation, find x:
\n" ); document.write( "8x + 2(2x) = 324
\n" ); document.write( ":
\n" ); document.write( "8x + 4x = 324
\n" ); document.write( ":
\n" ); document.write( "12x = 324
\n" ); document.write( "x = \"324%2F12\"
\n" ); document.write( "x = 27 big ones
\n" ); document.write( "then
\n" ); document.write( "y = 2(27)
\n" ); document.write( "y = 54 small ones
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\n" ); document.write( "Check solution in the total weight equation:
\n" ); document.write( "8(27) + 2(54) =
\n" ); document.write( "216 + 108 = 324 \n" ); document.write( "
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