Library / /332 of 475

, 1999

Number theory Difficulty 2.0 Junior Find the answer Canada

The time on a digital clock is 5:55. How many minutes will pass before the clock next shows a time with all digits identical?

(A) $71$ (B) $72$ (C) $255$ (D) $316$ (E) $436$

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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.