Question

A police jeep is chasing a culprit going on a motorbike. The motorbike crosses a turning at a speed of 72 km/h. The jeep follows it at a speed of 90 km/h, crossing the turning 10 second later than the bike. Assuming that they travel at constant speeds how far from the turning will the jeep catch up with the bike?

Please answer this fast. No spams please.

Answer 1

Solution :

Speed of motor bike=72 km/hr=72x5/18 =20 m/s

Speed of Jeep=90x5/18=25m/s

Let us assume that Jeep catches the bike at a distance of  X m from the turning.

Time taken to civer  distance X m =Distance/time

=x/20 sec

Since jeep starts 10 sec later , so it takes 10s less time to cover the equal distance

Time taken to cover X m will be =x/20 - 10

But from the jeep's speed it comes to be x/25 s

These two must be equal. Hence

x/20-10=x/25

x-200/20=x/25

x-200/4=x/5

5x-1000=4x

x=1000m=1km

∴Hence the jeep will catch up the bike at a distance of 1km

Answer 2

Speed of motor bike=72 km/hr=72x5/18 =20 m/s

Speed of Jeep=90x5/18=25m/s

Let us assume that Jeep catches the bike at a distance of X m from the turning.

Time taken to civer distance X m =Distance/time

=x/20 sec

Since jeep starts 10 sec later , so it takes 10s less time to cover the equal distance

Time taken to cover X m will be =x/20 - 10

But from the jeep's speed it comes to be x/25 s

These two must be equal. Hence

x/20-10=x/25

x-200/20=x/25

x-200/4=x/5

5x-1000=4x

x=1000m=1km

∴Hence the jeep will catch up the bike at a distance of 1km