In a 500 m race the ratio of the speeds of two contestants Ajmal and Badal is 3:4 . If Ajmal has a head start of 140 km then Ajmal wins by-
A
10m
B
20m
C
30m
D
60m
Correct Answer: 60m
To reach the winning post Ajmal will have to cover a distance of (500 - 140)m = 360 m. While Ajmal covers 3 m, Badal covers 4 m. While Ajmal covers 360 m, Badal covers (4/3×360)m = 480 m. Thus, when Ajmal reaches the winning post, Badal covers 480 m and therefore remains 20 m behind. ∴ Ajmal wins by 20 m. (ans)