1. Let A type X every minute, then B type X-12 every minute; Since the time for A to type 3,000 words is the same as that for B to type 2,400 words, 3,000/x = 2,400/(x-12), and both sides of the equation are divided by 600 at the same time to get 5/x=4/x- 12. When solving the equation, you get x=60, and b type 60- per minute.

2. Since Party A types 12 more words per minute than Party B, it takes 600/ 12 minutes =50 minutes for Party A to type 600 more words (3000-2400) than Party B; That is, within 50 minutes, A typed 3000 words and B typed 2400 words, so A typed 3000/50=60 words per minute and B typed 2400/50=48 words per minute.

Is the landlord detailed enough? I can't type 48 words per minute. Oh, it's very hard, hehe, give points!