Final answer:
To find the percentage of the world's population that lives in China, divide the population of China by the world population and multiply by 100. The percentage is about 19.12%.
Step-by-step explanation:
To find the percentage of the world's population that lives in China, you can divide the population of China by the world population and then multiply by 100.
Population of China: 1.3 x 10^9
World population: 6.8 x 10^9
Percentage of world population in China: (1.3 x 10^9 / 6.8 x 10^9) x 100 = 19.12%