Question

In a morning walk three persons step off together. There steps measure 80 cm, 85 cm, and 90 cm respectively. What is the minimum distance each should walk so that all can cover the same distance in complete steps?

Answer 1

We have to find the LCM of 40 cm, 42 cm and 45 cm to get the required minimum distance. Because we are asked the minimum distance Now, 40 = 2 × 2 × 2 × 5, 42 = 2 × 3 × 7 45 = 3 × 3 × 5 ∴ LCM (40, 42, 45) = 2 × 3 × 5 × 2 × 2 × 3 × 7 = 30 × 12 × 7 = 210 × 12 = 2520 
Minimum distance each should walk 2520 cm. so that, each can cover the same distance in complete steps.

Answer 2

we need to find the lowest common factor to get the minimum distance each should walk.