"1) How many persons live today in third world countries?"
Do you really believe that a true accurate number exists? With uneducated, illiterate people who don't even speak english in most of these places it would be too hard to get an accurate count from us (I doubt it is high on their governments priority). We probably don't even have a true number of people in our own country.
I would assume that people living in third world conditions would approach 2-5 billion (compared with our standard of living). I know the world population to be roughly 5-7 billion people depending upon who you ask. The United States population is approx. 270-320 million, depending upon your source. The population of India I have heard to be around 1 billion alone, and I know from a professor I had who spent time there that they use defecation as "heating oil" and their land is almost completely devoid of any plants or trees. When you throw in African countries, Middle Eastern countries, areas around the phillipines, and even parts of Mexico it is safe to say the numbers are very high.
"2) How many persons were living in those countries the year you were born? "
I was born in 1975. Populations have been booming exponentially due to lack of education, religious practices, and boredom (what else do poverty stricken have to do). I would not be suprised if the doubling time of those countries is around 30-40 years, which is why some of them are reaching their carrying capacity as we speak. Somalia, Ethiopia, and other countries I am sure we haven't even heard of because it would take time away from the latest NSYNC video, Presidential drug or sex scandal, or who will win the oscars. That stuff is too depressing for our culture. So to the best of my knowledge the populations for those countries were probably around 1-2.5 billion when I was born. That is based on estimations, a true number is probably not really known for a world census is very hard to come by.
"3) How did this state of affairs come to be? "
I suppose you would like to believe that these countries just didn't rise up and get on the capitalistic bandwagon, so to speak. You are probably of the school that thinks their government put them in this position because of their political ties and so forth. In all honesty I don't know why they are in the situaiton they are in. Maybe it was the flap of a butterflies wing that set forth a chain reaction of events. I do know that we (the U.S) are a small number of the total population and use up roughly 2/3 of the resources. I do know that it is in our best interest to convince other nations to give us their goods for our "friendship" and "protection". Our excesses have not helped the condition of the global community.
Hope that is what you wanted me to say
bye bye - Scotty