This is a question I came across in a lab report for my first high school physics course. And I'm a little stumped by it. So far the only way I know to get the average velocity is to add the final and initial velocities and divide by 2. Looking through my textbook and searching online I've come up empty so far. so I've come here for some answers. This is assuming constant acceleration and disregarding air resistance.
How to Find Average Velocity from Acceleration and Time
accelerationkinematicsvelocity
Best Answer
Assuming that your acceleration is constant, then you can simply use $\bar v = \dfrac{v_1+v_2}2$, and you can calculate both $v_1$ and $v_2$ by using the equation $v=at+v_0$.
Do note that if the acceleration is not constant, then the average acceleration is $\bar v = \dfrac{\Delta x}{\Delta t}$ where $\Delta x$ is the change in position.