Correct Answer:- 1900

Explanation:- A beats B by 1 km, means A travels 10 km in the same time that B travels 9 km. The ratio of speeds of A and B is 10 : 9. Similarly, the ratio of speeds of B and C is 10 : 9.

A : B = 10 : 9 B : C = 10 : 9

⇒ The ratio of speeds of A : B : C = 100 : 90 : 81

In the same time that A travels 100 m, C travels 81 metres

⇒ In the same time that A travels 10000 m, C would travel 8100 m or A would beat C by 1900 m. Ans: (1900)