on a morning walk 3 persons step off together and their steps measure 40 cm , 42 cm and 45 cm respectively what is the minimum distance each should walk so that each can cover the same distance in complete steps

The minimum distance that they all three should walk will be the L.C.M. of 40, 42, 45.

Since 40=2×2×2×5

42=2×3×7

45=3×3×5

∴ L.C.M. of 40, 42 and 45 = 2×2×2×3×3×5×7= 2520cm = 25.20m

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