How long are the energy resources of the earth like coal, petroleum and natural gas expected to last?

The energy resources of the earth like coal, petroleum and natural gas expected to last as follow:

Coal - 200 years

Explanation

The fossil fuels such as coal, petroleum and natural gas left in the earth are limited in quantity. It has been estimated that the world's coal reserves may last for the next 200 years, the known reserves of petroleum for about 40 years and the known reserves of natural gas for around 60 years.