To calculate the average velocity when you have two velocities and one acceleration, you can use the following formula:
Average Velocity = (Initial Velocity + Final Velocity) / 2
The initial velocity is the velocity at the starting point, and the final velocity is the velocity at the ending point. By adding the initial and final velocities and dividing by 2, you get the average velocity over the given time period.
It's important to note that this formula assumes constant acceleration. If the acceleration is not constant, or if the velocities are measured at different points in time, you would need additional information to calculate the average velocity accurately.