Ezekiel hikes as a hobby. This past summer, he did a challenging three-day hike across 50 kilometers of wilderness. The first day, he covered 10 kilometers of steep mountainside. The second day was flatter and he was able to cover half the full hike distance. How many kilometers did he have to hike on the third day to finish the hike? Let's think first. Chain of thought:
After the first day, Ezekiel had 50 - 10 = 40 kilometers of the hike left. On the second day, he covered 50 / 2 = 25 kilometers. Therefore, on the third day, he had 40 - 25 = 15 kilometers left to finish the hike.
Therefore, the answer is 15.