posted by Jason .
a car accelerates at a constant rate from zero to 26.7 m/s in 10 seconds and then slows to 19 m/s in 5 seconds. What is its average acceleration to the nearest tenth of a m/s^2 during the 15 seconds?
Avg. acceleration = (Velocity change)/time
= 19/15 = 1.27
-> 1.3 m/s^2 (rounding to nearest tenth)
Only the initial and final velocity matter when you want the average acceleration