Correct Answer: 11.52 km
Explanation:
Pawan's speed downstream = 24 + 4.8 = 28.8 km/h 
 Pawan's speed upstream = 24 - 4.8 = 19.2 km/h
 Let the required distance be x. 
According to the question. 
 x/28.8 + x/19.2 = 1 
 ⇒ (19.2x + 28.8x) / 552.96 = 1 
 ⇒ 19.2x + 28.8x = 552.96 
 ⇒ 48x = 552.96 
 ∴ x = 552.96/48 = 11.52 km
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