TOM traveled the entire 100 miles trip

TOM traveled the entire 100 miles trip. If he did the first 50 miles of at a constant rate 20miles per hour and the remaining trip of at a constant rate 50 miles per hour, what is the his average speed, in miles per hour?

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 #16267