The average speed of a car decreased by 3 miles per hour…

The average speed of a car decreased by 3 miles per hour every successive 8-minutes interval. If the car traveled 3.6 miles in the fifth 8-minute interval, what was the average speed of the car, in miles per hour, in the first 8 minute interval?

This problem repeats another one in the library (at most with different numbers), so it's left out of browsing.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #49541