Multiple Travellers problem

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Multiple Travellers problem

by Manish878 » Fri Oct 23, 2015 8:59 am
Hello,

I have a doubt regarding the following question.

Question: Ata and Carl both departed Townville at noon. Ata travelled by 100 kilometers per hour, and Carl travelled at 75 kilometers per hour. If Ata arrived at Villageton one hour earlier than Carl, what is the distance in kilometers, from Townville to Villageton?

Ata=100km/hr
Carl=75km/hr

carl's time: t
Ata arrived at villageton 1 hour "earlier".Therefore, the total time [t] for ata is = t - 1

Equation 1: (Ata)
D=Rxt
D=100x(T-1)
D=100t-100;

Equation 2: (Carl)
D=Rxt
D=75t

eq1=eq2
75t=100t-100
t=4.

The answer to the above problem is t=3...where am i going wrong?

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by Brent@GMATPrepNow » Fri Oct 23, 2015 9:54 am
Manish878 wrote:Hello,

I have a doubt regarding the following question.

Question: Ata and Carl both departed Townville at noon. Ata travelled by 100 kilometers per hour, and Carl travelled at 75 kilometers per hour. If Ata arrived at Villageton one hour earlier than Carl, what is the distance in kilometers, from Townville to Villageton?

Ata=100km/hr
Carl=75km/hr

carl's time: t
Ata arrived at villageton 1 hour "earlier".Therefore, the total time [t] for ata is = t - 1

Equation 1: (Ata)
D=Rxt
D=100x(T-1)
D=100t-100;

Equation 2: (Carl)
D=Rxt
D=75t

eq1=eq2
75t=100t-100
t=4.

The answer to the above problem is t=3...where am i going wrong?
You did everything perfectly.
In the video solution (https://www.gmatprepnow.com/module/gmat- ... /video/913), ATA's travel time is 3 hours.
In your solution, you have solved for Carl's travel time, and you got 4 hours. Ata's travel time is 1 hours less, so Ata's travel time is 3 hours.

If anyone else is interested, we answer this question three different ways in the video (https://www.gmatprepnow.com/module/gmat- ... /video/913)

Cheers,
Brent
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by [email protected] » Fri Oct 23, 2015 3:30 pm
Hi Manish878,

As Brent has pointed out, you did all of the 'math' correctly, but you lost track of what the specific question was asking for.

This is an important issue, especially in the Quant section (although it can apply to some RC and CR prompts as well). On many questions, one or more of the wrong answers will be the answer to a DIFFERENT question, so you have to be very careful about being sure that you're answering the question that is ASKED. Taking the necessary notes (including writing down what you're trying to figure out) should help you to avoid this issue going forward.

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by MartyMurray » Fri Oct 23, 2015 4:03 pm
One thing that I have noticed is that people sometimes get so excited, or relieved, at having done the tougher of the calculations necessary to get to an answer that they mess up the problem. They may answer the wrong question, or make a careless error in completing the question, or do something else that results in their either having to go back and fix something or choosing the wrong answer.

So remember to keep the question in mind and to stay calm and complete questions correctly.
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by Manish878 » Sun Oct 25, 2015 12:09 am
Hello,

I am from the arts background; the last time i math problem was in my 10th grade :D Anyway.i really appreciate your help in solving the problem. Thank you.

Regards,
Manish A

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by [email protected] » Sun Oct 25, 2015 9:31 am
Hi Manish,

Many Test Takers have 'rusty' math skills when they start studying for the GMAT. There are plenty of tools and resources that you can use to build those skills back up though. If you'd like some extra free help building up your math abilities, then I suggest that you use Khan Academy (www.khanacademy.org). While the site is vast, you can find some appropriate math practice in the Arithmetic, Algebra and Geometry sections. For GMAT-related questions, posting in these Forums is a great way to learn additional Tactics, gain insights, learn patterns and 'secrets', etc.

1) How long have you been studying?
2) When are you planning to take the GMAT?
3) What is your goal score?

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by Matt@VeritasPrep » Sun Oct 25, 2015 10:14 pm
Manish878 wrote:Hello,

I am from the arts background; the last time i math problem was in my 10th grade :D Anyway.i really appreciate your help in solving the problem. Thank you.

Regards,
Manish A
Never fear - math is more artistic than you'd think. Just like any art, it requires a sound grasp of the basics and a lot of creativity and ingenuity.

I didn't do much math until I was in my late 20s -- I was a literature guy -- but I fell in love with it once I got away from my math teachers!

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by Brent@GMATPrepNow » Mon Oct 26, 2015 6:43 am
Matt@VeritasPrep wrote: Never fear - math is more artistic than you'd think. Just like any art, it requires a sound grasp of the basics and a lot of creativity and ingenuity.
I 100% concur with Matt. In fact, when I received my mathematics degree at the University of Victoria, I was given the choice to either receive a BSc or a BA.

Cheers,
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