Cooking at two different temperatures

I would cook both at 400 degrees. After the indicated one hour for the potatoes, remove them. Chicken might also be ready at one hour @ 400 degrees versus one hour broken down into 15 minutes @500 plus 45 @ 350. I confess i am not doing any math but just using my cooking intuition. You can always check chicken earlier. I think internal temperature of chicken should be no less than 165 but you can google to verify.