The train departs from station A and within 6 seconds reaches a speed of 20 m / s. Then, for 1 minute, he walks at this speed

The train departs from station A and within 6 seconds reaches a speed of 20 m / s. Then, for 1 minute, he walks at this speed, and in front of station B, for 6 s, he moves equally slow with the same acceleration. Determine the distance between stations.

Acceleration in the first section
a = (V-Vo) / t
a = 20/6 = 3.333333 m / s2
Distance traveled during this period of time
s = Vo * t + (a * t ^ 2) / 2
s = (3.333333 * 6 ^ 2) ÷ 2 = 60
then moved at a constant speed for 60 seconds
s = 20 * 60 = 1200 meters
In the last section, it moved equally slowly with a = -3.333333 m / s2
We calculate the distance using the formula:
s = Vo * t + (a * t ^ 2) / 2
s = 20 * 6 + (- 3.333333 * 6 ^ 2) ÷ 2 = 60 meters
We summarize the distance traveled at each site
s = 60 + 1200 + 60 = 1320 meters