There is also the word "far more". For instance, 1. There were far more men there than their were women. You use it the same way as "far fewer".

Some more examples: 1. There were far fewer people online last night who have Skype than those who do not. 2. There were far fewer boys than girls at the their party. 3. He said there were far fewer students attending the conference this year than there were last year. 4. I don't know if/whether there were far fewer students there this year than there were last year. (Note that "there" appears 3 times in this sentence. The first and last one are required.) 5. I don't know if/whether there were far fewer students at the conference this year than there were last year. 6. Does he know if/whether there were far fewer students at the conference this year than there were teachers? 7. I went to a party where there were far fewer girls than there were guys. 8. I saw that there were far fewer vendors at the Star Trek convention in Boston this year than there were last year when I went with my friend Adam. 9. If there are far fewer women there than men this year, then I think we should change our advertising campaign strategy to target primarily men next year. 10. There are far more bad example sentences in this Italian-English dictionary than there are correct and useful ones.

So: 1. many more student = far more students = a lot more students 2. far fewer students = a lot fewer students = many fewer students (although I don't hear "many fewer" that much and it sounds a little unnatural for my area) 3. much more milk = far more milk = a lot more milk 4. much less milk = far less milk = a lot less milk

It should be "There were far fewer women than men."