A policeman goes after a thief who has 100 m start . If the policeman runs a km in 8 min and the thief runs a km in 10 min , then the distance covered by thief before he is being caught is :
Answer & explanation
Correct answer: option 3
Relative speed when they move in same direction
Relative speed = \(\frac{1000}{8}\) - \(\frac{1000}{10}\)
= \(\frac{5000-4000}{40}\)
= \(\frac{1000}{40}\) m/minute
Required time = \(\frac{100}{\frac{1000}{40}}\) = 4 m/minute
Distance travelled by thief = \(\frac{1000 \; × \; 4 }{10}\) = 400m