document.write( "Question 324914: If the difference between one-third of a number and one-seventh of that same number is 8, then what is the number?\r
\n" ); document.write( "\n" ); document.write( "(A) 12 (B) 21 (C) 30 (D) 42 (E) 56\r
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Algebra.Com's Answer #232630 by vleith(2983)\"\" \"About 
You can put this solution on YOUR website!
Let x be the number. You are told
\n" ); document.write( "\"x%2F3+-+x%2F7+=+8\" find a common denominator. Since 3 and 7 are relatively prime (and also really prime), that demoninator is 3*7 = 21
\n" ); document.write( "\"7x%2F21+-+3x%2F21+=+8\"
\n" ); document.write( "\"4x%2F21+=+8\"
\n" ); document.write( "\"4x+=+168\"
\n" ); document.write( "\"x+=+42\"
\n" ); document.write( "Check your answer
\n" ); document.write( "what is the difference between 42/3 = 14 and 42/7 = 6 equal 8??
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