RAS question
The average annual rainfall of Rajasthan is approximately:
Correct answer: (A) 57 cm.
Rajasthan's average annual rainfall is approximately 57 cm, making 57 cm the closest stated value for the state's average rainfall.
Explanation
Rajasthan receives relatively little rainfall, and the amount varies considerably across the state. Its average annual rainfall is approximately 57 cm, or about 575 mm; this does not mean that every district receives the same amount. Rainfall differs greatly from Jaisalmer to Jhalawar, reflecting the contrast between the arid west and the wetter southeast. Therefore, 57 cm is the closest option to the state average; the other values either understate or overstate it.
Why the other options are wrong
- (B) 110 cm is far above Rajasthan's approximate annual average of 57 cm (about 575 mm). It may be closer to rainfall in a wetter area, but it is not the state-wide average asked here.
- (C) 31 cm is below the state average and is closer to the lower rainfall of western Rajasthan than to the approximate average for the whole state.
- (D) 85 cm is considerably higher than Rajasthan's approximate annual average of 57 cm (about 575 mm), so it overstates the state average.
Concept
This tests two basic aspects of Rajasthan climatology: the state's average rainfall and the contrast between the arid west and the wetter southeast. RAS repeatedly asks about such averages because they connect physical geography with agriculture, irrigation, drought risk, water-resource planning and regional development.