It's not too far. 5 minutes if you walk fast, 10 if you kinda dawdle. If you're late the first time, the tutor should be sympathetic, and that will give you a good estimate of how long it should take. If you sit toward the back of the lecture hall, and you know you can't make it back in time, just leave a few minutes early.The lecture is at Haymarket and the tutorial is at Broadway. Hopefully it's not too hard or time-consuming to get between them!