Three boys step off together from the same spot. Their steps measure 63 cm, 70 cm and 77 cm respectively. What is the minimum distance each should cover so that all can cover the distance in complete steps?

Explanation

To find the minimum distance that each boy should cover so that all can cover the distance in complete steps, we need to calculate the Least Common Multiple (LCM) of their step lengths: 63 cm, 70 cm, and 77 cm.

### Step-by-Step Solution:

**Step 1: Prime Factorization of Each Step Length**
- **63 cm**:
- 63 = 3 × 21
- 21 = 3 × 7
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