Baking things often works at a fairly wide range of temperatures. What matters I that the inside of what's being baked gets to a certain temperature and you can

Baking things often works at a fairly wide range of temperatures. What matters I that the inside of what's being baked gets to a certain temperature and you can achieve that with different oven temperatures. It just takes a different amount of time. Then there are techniques like poking a fork or a toothpick into your cake to see whether the dough sticks to it or not. If not, it's done. And then there's trial and error and experience. Others mentioned a gas oven which a) doesn't have a precise temperature and b) often an uneven heat distribution. Works just as well, though, with a bit of learning.