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Problem 357

Combinatorics Difficulty 2.0 Find the answer CEMC Gauss (Grade 8) · Canada · 2010

The time on a digital clock is $10:25$ . In minutes, what is the shortest length of time until all the digits on the clock will be equal to one another? (A) $36$ (B) $107$ (C) $86$ (D) $46$ (E) $187$

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