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UKMT Grey Kangaroo, 2021

Algebra Difficulty 2.0 Junior Find the answer United Kingdom

In a particular fraction the numerator and denominator are both positive. The numerator of this fraction is increased by 40%. By what percentage should its denominator be decreased so that the new fraction is double the original fraction?

(A) $10\%$ (B) $20\%$ (C) $30\%$ (D) $40\%$ (E) $50\%$

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