Miles wise its between 10 and 20 depending on what freeway you take. If you take 110N, its about 10-12 miles. 10 E can be between 10-20 ---- of course it depends on where you are exactly...Time wise, in rush hour traffic you can expect to spend 30-40 mins to go say 15 miles.
Depends where at you live in Pasadena and where you want to be in LA, I live in Pasadena, and it takes about 12 minutes to get into La (taking the 110 fwy) buttt it ranges as to where I am going in La and what time of day it is... plan wisely, nothing like the LA traffic. ;)
Depends where in LA. LA is 30 miles east to west.