Circular track

This topic has expert replies
User avatar
Senior | Next Rank: 100 Posts
Posts: 67
Joined: Mon Aug 16, 2010 4:42 am

Circular track

by Viper83 » Tue Jun 21, 2011 7:43 am
2 cars drive in opposite direction around a circular track, starting at the same time. Car A drives at a speed of 3 km/h and car B drives at a speed of 1 km/h. The Track has a diameter of 4 km. After how long will the cars meet?

I solved this questions the following way (please tell me whether my approach is correct):

Diameter=4
Circumference=4pi

Speed of both cars=1+3=4

distance=rate*time

Therefore, they will meet after 4pi/4=pi hours. Answer: they will meet after pi hours.

Is my approach correct?

Thanks
Source: — Problem Solving |

Legendary Member
Posts: 1448
Joined: Tue May 17, 2011 9:55 am
Location: India
Thanked: 375 times
Followed by:53 members

by Frankenstein » Tue Jun 21, 2011 7:44 am
Correct!
Cheers!

Things are not what they appear to be... nor are they otherwise

Junior | Next Rank: 30 Posts
Posts: 23
Joined: Wed Feb 27, 2008 6:01 pm
Thanked: 1 times
Followed by:1 members

by sushbis » Tue Jun 21, 2011 8:45 am
if the Q is "starting at the same time", then i doubt your answer is the correct one. But if it is "starting from the same point", then it is correct.

User avatar
Senior | Next Rank: 100 Posts
Posts: 67
Joined: Mon Aug 16, 2010 4:42 am

by Viper83 » Tue Jun 21, 2011 9:28 am
Hi Sushbis, yes you are right. It should be the same time and from the same point