Question 1
Medium
In a 1 km race, Usha beats Vani by 20 s and Wahida by 40 m. If Vani's speed is 4 m/s, by how many metres would Wahida beat Vani in a 1 km race?
A
41.67 m
B
40 m
C
43.48 m
D
38.4 m
Correct Answer:
A
Explanation:
Vani's time = 1000/4 = 250 s, so Usha's time = 230 s; Wahida covers 960 m in 230 s.
Wahida's time for 1000 m = 1000 × 230/960 = 239.58 s.
In that time Vani covers 4 × 239.58 = 958.33 m, so Wahida beats her by 1000 − 958.33 = 41.67 m.