Library / /245 of 472

, 1999

Number theory Difficulty 2.0 Junior Find the answer Canada

The number of solutions $(P, Q)$ of the equation $\frac{P}{Q} - \frac{Q}{P} = \frac{P+Q}{PQ}$ , where $P$ and $Q$ are integers from 1 to 9 inclusive, is

(A) $1$ (B) $8$ (C) $16$ (D) $72$ (E) $81$

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project. Solutions are the publisher's, linked not copied.