At the opening of a trading day at a certain stock exchange…

At the opening of a trading day at a certain stock exchange, the price per share of stock K was $10. If the price per share of stock K was $15 at the closing of the day, what was the percent increase in the price per share of stock K for that day?

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 #47500