Enigma 1761: Clock work
7 August 2013
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From New Scientist #2929, 10th August 2013 [link]
The clock in Simpson Mall has hour, minute and second hands. Little Esu climbs onto the hour hand at 12.01 pm, and stays on it until the minute and hour hands are aligned. At that instant, Esu jumps on to the minute hand and rides on it until the hour and minute hands are aligned and then jumps on to the hour hand. In this way, Esu changes positions between the hour and minute hands whenever they are aligned. Finally, Esu jumps off the clock when all three hands are aligned.
For how many minutes in total did Esu ride the minute hand?