Why do the major deserts o f th world occur around 25 degree north or south?

Answer 1

Since the area on the equator receives the most direct sunlight, the humid air heats up and rises. In the upper atmosphere it condenses into clouds and rain falls in the tropics. The now-dry air moves to about 30 degrees north and south and sinks, forming a desert.

Answer 2

deserts form around 10-30 degrees latitude because this region is the subtropics

Answer 3

Air at the equator rises and forms rain clouds which drop their rainfall in the tropics. The now-dry air moves to about 30 degrees north and south where it sinks, forming deserts.