A mother takes two strides to her daughter’s three. If they set out walking together, each starting with the right foot, when will they first step together with the left?
Never. After the mother’s first four strides and the daughter’s first six, they will again step together with the right foot, and the cycle repeats. Nowhere in that interval do they step together with the left foot.
October 21, 2012 | Puzzles
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