Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized for You
we will pick new questions that match your level based on your Timer History
Track Your Progress
every week, we’ll send you an estimated GMAT score based on your performance
Practice Pays
we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
It appears that you are browsing the GMAT Club forum unregistered!
Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club
Registration gives you:
Tests
Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.
Applicant Stats
View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more
Books/Downloads
Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!
Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:
Rate Question, please help! [#permalink]
07 Oct 2006, 20:02
This topic is locked. If you want to discuss this question please re-post it in the respective forum.
Hi, got stumped on this one. Any help would be really appreciated it.
2 Trains, X&Y, start simultaneously on opposite ends of a 100-mile route and travled toward each other on parallel tracks. Train X, traveling at a constant rate, completed the 100 mile trip in 5 hours. Train Y, also traveling at a constant rate completed the 100 mile trip in 3 hours. How many miles had train X traveled when it met Train Y?
Rate x Time = Distance
Train X 5 x t = d
Train Y 3 x t = 100-d
The only variable they have in common is that both trains have been travelling for the same amount of time...thus, set each equation equal to each other in terms of d.
so Train X = t = d/5
and Train Y = t = (100-d)/3
Set each equation equal to each other:
d/5 = (100-d)/3
Cross multiply and you get:
3d = 500 - 5d
Solve for d and you get 62.5. Thus the answer is 62.5
Clearly the speeds ratio of A and B is 3:5 So distance covered by them when they meet each other also will be in the ration 3:5
So distance covered by A is 3/8 x 100 = 37.5
Hence A.
Keep it simple....... Get the concepts of ratios.............Save time in the exam
Regards,
Cicerone Where do you get 3/8 from? I like your ratio method of doing this.
Hey look at the bold part
Since the distance is shared in the raio of 3:5
A should cover 3/8 and in the same time B will cover 5/8 ............. _________________
Clearly the speeds ratio of A and B is 3:5 So distance covered by them when they meet each other also will be in the ration 3:5
So distance covered by A is 3/8 x 100 = 37.5
Hence A.
Keep it simple....... Get the concepts of ratios.............Save time in the exam
Regards,
Yes, it works in this example, but it is better to have a clear concept of solving such problems. This ratio example won't work for other "rate" problems...
Clearly the speeds ratio of A and B is 3:5 So distance covered by them when they meet each other also will be in the ration 3:5
So distance covered by A is 3/8 x 100 = 37.5
Hence A.
Keep it simple....... Get the concepts of ratios.............Save time in the exam
Regards,
Yes, it works in this example, but it is better to have a clear concept of solving such problems. This ratio example won't work for other "rate" problems...
Hey SimaQ, please do not say this..............
Any question form Time and Distance out of Speed , Distance and Time if one of them is constant, i bet i will do it using ratios only..............
Why don't u try to test me........ _________________
cicerone's method is neater but this is how i did it. trick to remember with this type of question where 2 things travel towards each other is that together they travel the total distance, whether its lifts, trains, cars, water going down a pipe, frogs etc
so
where t = time
100/5 t + 100/3 t = 100
300/15 t + 500/15 t = 100
t = 1500/800 = 15/8