Two trains, each of length ` 100 m`, are running on parallel tracks. One overtakes the other in `20 second ` and one crosses the other in `10 second`. Calculate the velocities of two trains.

Explanation

To solve the problem of two trains overtaking and crossing each other, we can break it down into steps.

### Step-by-Step Solution:

1. **Identify Given Information**:
- Length of each train = 100 m
- Time taken to overtake = 20 seconds
- Time taken to cross each other = 10 seconds
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