Well, your friend has two options.
1)Content Writing
Freshers are paid $1-2 per 500 words.
Established writers are paid $3-5 per 500 words.
With some time and effort and the right techniques, you can end up having more work than you can handle, so you can earn decently.
2)Copywriting
The Indian market is really small and the pay starts at 50p per word. However, you will find it really difficult to find any work, especially unless you are placed from a DU college to a Journo company etc. Such rates are only given to magazine writers/journalists and they usually do at most 1 article a week on an average, so that is like 1 hour a work a week but Rs.1000-2000 per month.
The problem here is not with the Earning-Time ratio, but with the amount of work. You won't make more than very little money (at least in the first few months/years, unless you are really lucky) because there isn't much work.
3)Copywriting for US/UK clients
Normally Indians aren't given a chance.
1. Natives know when a native writes and can separate even award winning writers from natives, because of the style of writing.
2. You don't have an office abroad and can't meet them in person.
So you can forget about this. However, this fetches anything from $10-100+ per 500 words. However, this path doesn't exist for your friend.
IMO
If your friend has enough time, he can easily work for Rs.70-100 per article (I don't pay that much though) if he is really good and is able to find good clients. Because most clients won't pay more than this for bulk work. $5 = Rs.225 is no longer the norm, it is an ideal rate which very few established writers charge today, and even fewer actually get work at that rate, leave alone all the work at that rate.
Getting work isn't difficult, but having unrealistic expectations will take you nowhere.
It is like doing BTech from IP University, topping the college and asking for a starting package of 15 LPA. People will just ignore you. That is exactly the case.
Even if you calculate at Rs.100 per hour, and you work 4 hours a day, that is a good 10k a month if you work 6 days a week. And that is at just rs.50 per article. Even if it is a little more, you can really increase your income. And for a person who isn't even a graduate, I don't think that an income of 10k pm is that bad, that too just working part time.
Even people who teach others as tutors (non IITians), the average tutor just gets Rs.200-300 per hour and needs to pay for his travel expenses, visit somebody else's house, lose his freedom, ignore his ego, and for that he just makes at most double the amount. And there too, you don't have unlimited work. So at the end of the day you may work a little less, but you don't make much more.
I would suggest your friend to be realistic. If he wants Rs.5 per word, ask him to do a BA Journo Hons from an Ivy League and he will definitely make it to that stage or even much higher level very soon. But atm, NO!
He's a good writer.