When Shanti had crossed the finish line, she was a distance of 250 m ahead of Belle
We are given;
Length of Race = 1000 m
When nina crossed the finish line, she was 200 m ahead of Shanti and 400 m ahead of Belle.
Thus;
Shanti had run 4/5 of the race when Nina finished.
So, if Nina's time was x, then by variation, we can say that;
Time it took Shanti to finish the race = 5/4x
So, Belle had run 5/4 * 600 = 750 meters when Shanti finished.
Thus, means Shanti was; 1000 - 750 = 250m ahead of Belle.
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