During a trip, Francine traveled x percent of the total distance at…

During a trip, Francine traveled x percent of the total distance at an average speed of 20 miles per hour and the rest of the distance at an average speed of 80 miles per hour. In terms of x, what was Francine’s average speed for the entire trip?

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 #11347