an automobile travels between the 176.5-m and 295.7-m markers on the highway in 12.4s ...

I've got a great idea! Let's calculate the car's average speed!

Average speed = (distance covered) / (time to cover the distance)

Distance covered = (position at the end) - (position at the beginning)

= (295.7 m) - (176.5 m) = 119.2 m

Average speed = (119.2 m) / (12.4 s) = 9.61 'm' per 's'.