The difference between a positive proper fraction and its reciprocal is 9/20. The fraction is  Choose one.
A) 4/5 B) 7/11 C) 7/13 D) 7/15 E) 8/11
Let the required fraction be x. Then	1	- x =	9   x	20   1 - x2	=	9   x	20   20 - 20x2 = 9x   20x2 + 9x - 20 = 0   20x2 + 25x - 16x - 20 = 0   5x(4x + 5) - 4(4x + 5) = 0   (4x + 5)(5x - 4) = 0   x =	4/5   4/5)
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The difference between a positive proper fraction and its reciprocal is 9/20. The fraction is