Question

A car, moving along a straight stretch of highway,
begins to accelerate at 0.024 m/s
2
. It
takes the car 61.8 s to cover 1 km.
How fast was the car going when it first
began to accelerate?

Answer 1

average velocity=1000m/61.8 sec=16.18m/s= 1/2 (vf+vi) or
vf+vi=32.36m/s
Now, vf=vi+at
vf-vi=.024*61.8=1.48

so now you have two equations, subtract the second from the first.
2Vi=32.36-1.48 and solve.