Help!!! 4.7 lb. rib roast in oven now. No meat thermometer!!

[marrowme]

i just put a 4.7 lb. standing rib roast in the oven. 450 degrees for 15 min then lower to 325 degrees. My meat thermometer is not here.(long story) how long should i cook this? i cant recall exactly how long it took in the past. is 18-20 min. per pound about right? thanks

[Gio]

I say 20 minutes a lb is about right... without a thermometer at hand. Hope I'm not too late for you.