Mountain climber Joe climbed to a mountain peak that was1200 feet above its base and 1500 feet east of its base. Mountain climber Bob climbed to a mountain peak that was 900 feet above its base and 1000 feet east of its base.

Who climbed a steeper mountain? Explain.

I wanna say it's Joe but I also feel like I'm wrong, and I have no idea how to explain my answer lol.