3 minutes is a little slow - RC does tend to take a bit more time on account of having to read the passage, but it shouldn't take 3 minutes. I'd say to aim for 2 , or even 1.5 minutes while practising.
Try this out - the first time you go over the passage, skim through it really quickly. Don't try to catch everything that's going on; just speed your way through it as quickly as you can, while understanding the general gist of what's going on in the passage. Next, answer each question in turn, and refer to the areas which the question specifically outlines as being relevant.
I'm not sure if this will work for you, but you should give it a try anyway to see if your speed and/or accuracy improve.