Is it normal for asian baby boy to weigh 15.5 lbs at 4 months as he was born 10 days early with 7.6 lbs weight?

He is not fat,his length approx 65 cm at 4 months now,im only 5'5" and hubby is 5'8" only..were both asians,my friends say he is big (tall) for his age.whenever i searched the net,i always see very big numbers for baby weight and height maybe becos we r asians we tend to be smaller..thanks..he also drinks around 24 to 30 oz of formula depending whether he is strolling with us in the mall or sleepind during car trips..