A dog saw a cat at a distance of 280 m. The cat started running at the speed of 10 km/h and the dog also ran to catch it with the speed of 24 km/h. How much time will the dog take to catch the cat?
Answer & explanation
Correct answer: option 3
We know that ,
Speed = \(\frac{Distance}{Time}\)
To convert km/h into m/sec
10 km/h = 10 × \(\frac{ 5 }{18}\) m/sec = \(\frac{ 25 }{9}\) m/sec
24 km/h = 24 × \(\frac{ 5 }{18}\) m/sec = \(\frac{ 20 }{3}\) m/sec
As both moves in same direction,
So relative speed = \(\frac{ 20 }{3}\) - \(\frac{ 25 }{9}\)
= \(\frac{ 60 - 25 }{9}\)
= \(\frac{ 35 }{9}\) m/sec
Time = \(\frac{ 280 × 9 }{35}\)
= 72 seconds
= 1.2 minute