Pay close attention to the #'s they are different. HELP?

Question

Rocket-powered sleds are been used to test the

responses of humans to acceleration. Start-

ing from rest, one sled can reach a speed of

469 m/s in 2.32 s and can be brought to a stop

again in 2.23 s.

Find the acceleration of the sled while ac-

celerating. Answer in units of m/s2.

Answer 1

Acceleration is change in speed / the time spent for this change

Simply, divide 469 m/s by 2.32 s, and you will get the acceleration in m/s2 . There is no need for converting units.

Answer 2

Speeding up: 469/2.32 = 202 m/s2

Slowing down: 469/2.23 = 210 m/s2 in the opposite direction.

The second one might be described as negative: -210 m/s2.

Slowing down is also accelerating.