It took only _____ years for world population to rise from 5 billion to 6 billion.
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 12
World population took only 12 years to grow from 5 billion to 6 billion, while it took more than a million years to reach the first billion.
Note: This question is taken from the pre-rationalised NCERT book. The latest edition (2026-27) does not have this part. An extract of the pre-rationalised NCERT book is given below for the benefit of students.
Pre-rationalised NCERT: “DOUBLING TIME OF WORLD POPULATION … It took more than a million years for the human population to attain the one billion mark. But it took only 12 years for it to rise from 5 billion to 6 billion.” |