Posted by Jay on .
A car accelerates at a constant rate from zero to 29.3 m/s in 10 seconds and then slows to 20 m/s in 5 seconds. What is its average acceleration to the nearest tenth of a m/s^2 during the 15 seconds?
Answer is 1.3....not sure how to get to it.
I am using the formula
a= (V sub2  V sub1) / (T sub2  T sub1)

Physics 
bobpursley,
a=(20)/15=1.3