Kinematics Question

1. The problem statement, all variables and given/known data

Dave and Andrew are racing. Dave running at a constant speed of 20m/s is passed by Andrew. 2.0s after Andrew passes, Dave accelerates at 1.0m/s^2 until he catches up with Andrew 25s later. What is Andrew’s velocity (he does not accelerate)?

2. Relevant equations

Kinematics Formulas.

3. The attempt at a solution
d=vit+1/2at^2
=(20)(25)+1/2(1)(25)^2
=812.5

Dave travels 812.5m.
v=d/t
=(812.5)(25+2)
=30.7m/s

I’m not sure if the way I did it was correct. Can someone please tell me how to do it. If you think I’m right though can you please tell me. Thanks!!

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