document.write( "Question 1185209: In a box, there was a total of 2 353 blue and black marbles. Oliver took 3/7 of the blue
\n" ); document.write( "marbles and 455 of the black marbles. After that, the number of blue marbles left was 2/3
\n" ); document.write( "the number of black marbles left. How many black marbles were there in the box at first?\r
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Algebra.Com's Answer #815993 by greenestamps(13200)\"\" \"About 
You can put this solution on YOUR website!


\n" ); document.write( "The response from tutor @ikleyn shows a straightforward setup and solution for the problem.

\n" ); document.write( "I decided to just try a very different setup to see if the path to the solution was any easier....

\n" ); document.write( "After Oliver took 3/7 of the blue marbles, 4/7 of them were left; those 4/7 of the blue marbles were 2/3 of the number of black marbles left.

\n" ); document.write( "To use \"nice\" numbers, then, let the number of blue marbles left after Oliver took some be 4x; then the number of black marbles left was 6x. So

\n" ); document.write( "4x = blue marbles left
\n" ); document.write( "6x = black marbles left

\n" ); document.write( "Then

\n" ); document.write( "7x = blue marbles originally
\n" ); document.write( "6x+455 = black marbles originally

\n" ); document.write( "The total number of marbles originally was 2353:

\n" ); document.write( "\"7x%2B6x%2B455=2353\"
\n" ); document.write( "\"13x=1898\"
\n" ); document.write( "\"x=1898%2F13=146\"

\n" ); document.write( "ANSWERS: The numbers of marbles in the box originally were
\n" ); document.write( "blue: 7x = 7(146) = 1022
\n" ); document.write( "black: 6x+455 = 6(146)+455 = 1331

\n" ); document.write( "The algebra ended up being easier than with the solution shown by the other tutor; but it took more time to figure out how to set the problem up....

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\n" ); document.write( "The point of my response:

\n" ); document.write( "Never be afraid of looking at different ways of doing things -- that's how progress is made.

\n" ); document.write( "(If we never looked for better ways to do things, we would still all be living in caves....)

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