Choose the correct option:
In a race of $200$ meters, A beats S by $20$ metres and N by $40$ metres. If S and N are running a race of 100 metres with exactly the same speed as before, then by how many metres will S beat N?
when A covers 200 m, S covers only (200-20)=180 m
and N covers only (200-40)=160 m
=> When N covers 160 m, S covers 180 m
=> When S covers 100 m, N covers (160 / 180) × 100 = 88.88889 m
Hence, S beats N by 100 - 88.88889 = 11.11 metre.
Option A is the Correct Answer.