document.write( "Question 980526: A person spent rs 564 buying pens and pencils. If the cost of each pen is rs 7 and each pencil is rs 3 and if the total number of things bought was 108, how many of each did he buy? \n" ); document.write( "

Algebra.Com's Answer #601644 by Cromlix(4381) $\"\"$ $\"About$

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Hi there,
\n" ); document.write( "Pen cost rs7
\n" ); document.write( "Pencil cost rs3
\n" ); document.write( "Total number of things = 108
\n" ); document.write( "The person spent rs 564
\n" ); document.write( "Make pens = x
\n" ); document.write( "Make pencils = y
\n" ); document.write( "x + y = 108......(1)
\n" ); document.write( "7x + 3y = 564.....(2)
\n" ); document.write( "Multiply (1) by 7
\n" ); document.write( "7x + 7y = 756.....910
\n" ); document.write( "7x + 3y = 564
\n" ); document.write( "Subtract (2) from (1)
\n" ); document.write( "....4y = 192
\n" ); document.write( "....y = 48
\n" ); document.write( "Substitute y = 48
\n" ); document.write( "into Equation (1)
\n" ); document.write( "x + y = 108
\n" ); document.write( "x + 48 = 108
\n" ); document.write( "x = 108 = 48
\n" ); document.write( "x = 60.
\n" ); document.write( "Therefore:
\n" ); document.write( "48 pencils were bought
\n" ); document.write( "60 pens were bought.
\n" ); document.write( "Hope this helps:-) \n" ); document.write( "

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