Answer:
6 billion
Step-by-step explanation:
The world's population reached its first billion in 1804. By the year 1960, there were approximately three billion of people on earth. By the year 1999, the population grew to 6 billion.
According to recent prognostics, by the year 2024, the world's population would reach eight billion people.
The world population is the total number of humans currently occupying the earth. The highest population growth rates happened between the years 1950-1970.