document.write( "Question 858120: Mr Brown gave a test with 30 questions worth 100 points. If some of the questions were worth three points and the rest worth 5 points, how many questions of each value did he have? \n" ); document.write( "

Algebra.Com's Answer #517057 by ben720(159) $\"\"$ $\"About$

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As the only types of questions were 3 points or 5 points, if you
\n" ); document.write( "Let X = how many 3-pointers there are
\n" ); document.write( "then the rest, or 30-x, must be 5-pointers.
\n" ); document.write( "The equation is 3*(number of 3-pointers) + 5*(number of 5-pointers) = total points.
\n" ); document.write( "Substitute
\n" ); document.write( " $\"3x+%2B+5%2830-x%29+=+100\"$
\n" ); document.write( "Distribute
\n" ); document.write( " $\"3x+%2B+150+-+5x+=+100\"$
\n" ); document.write( "Combine like terms
\n" ); document.write( " $\"-2x+%2B+150+=+100\"$
\n" ); document.write( "Add 2x to both sides
\n" ); document.write( " $\"150+=+100+%2B+2x\"$
\n" ); document.write( "Subtract 100 from both sides
\n" ); document.write( " $\"50+=+2x\"$
\n" ); document.write( "Divide both sides by 2
\n" ); document.write( " $\"25+=+x\"$
\n" ); document.write( "3pointers = x, 5-pointers = 30-x
\n" ); document.write( "There were 25 questions worth 3 points and 5 worth 5 points. \n" ); document.write( "

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