Cook a smoked ham and scalloped potatoes
Your question is a little bare, I'm going to assume you are asking whether you can cook these together, and if so which temperature you should pick. Keeping in mind you should take the ham out 30 minutes before you serve it to let it rest the potatoes will be in the oven for 30 minutes by themselves, so start the potatoes in the 375&deg;F oven, then turn it up to 400 after the ham is out. A 25 degree difference isn't going to make much difference to your potatoes, maybe 5 minutes extra cooking time, if that.