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**infinitebrain****Member**- Registered: 2008-07-01
- Posts: 153

Bob left Colorado City, TX at 5:00 am driving towards Amarillo at an average speed of 68 mph. His sister left 5 minutes later and drove at an average rate of 75 mph. If Amarillo is 232 miles from Colorado City, how far were Bob and his sister from Amarillo when she caught up to him?

Here are the answer choices:

a. 178.43 miles

b. 60.71 miles

c. 115.49 miles

d. 53.57 miles

e. 171.29 miles

The only thing I'm really confused about is how do you model that she left 5 minutes later on a calculator?

The best thing about life is you don't know what to expect

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,918

You could say that the time she has spent since starting the trip till they meet is 5 minutes shorter than the time he has spent since starting the trip till they meet.

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**infinitebrain****Member**- Registered: 2008-07-01
- Posts: 153

I keep plugging it in but it keeps saying they met at 48.5 miles, which doesn't connect with any answer choices. So, how am I plugging it in wrong?

The best thing about life is you don't know what to expect

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,918

How are you setting up the equation?

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,788

Hi;

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 6,872

hi infinitebrain,

I always like to draw a distance / time graph for these questions. see below.

Say the distance from Colorado when she overtakes is D miles and T hours after Bob starts.

Once you have worked out D, don't forget to give the answer from Amarillo.

Bob

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

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**infinitebrain****Member**- Registered: 2008-07-01
- Posts: 153

ohh! I get it Bob! I was confused on how you plug in the second equation, because I kept plugging in 75x - 5. Thank you all for helping me!

*Last edited by infinitebrain (2012-11-11 11:47:00)*

The best thing about life is you don't know what to expect

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,918

bobbym wrote:

Hi;

I am getting

as the answer...Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 6,872

Bob

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,788

Hi anonimnystefy;

how far were Bob and his sister from Amarillo when she caught up to him?

You are correct I did not read that part of the problem. Very good!

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 6,872

Well, it was easy for me, as I remember that trip well. My sister was still doing her hair or something when I set off. As you can see, she drives somewhat recklessly, with only a nice hair do and a winning smile to protect her from an angry state policeman.

Bob

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,788

Hi;

I only drove through Texas once and was never in Colorado City, I was close by in Sweetwater though.

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 6,872

hi,

Wiki says Sweetwater has a quidditch team. Is that why you went there?

Bob

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,788

Hi Bob;

Not exactly, just passing through.

**In mathematics, you don't understand things. You just get used to them.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,918

bob bundy wrote:

hi,

Wiki says Sweetwater has a quidditch team. Is that why you went there?

Bob

Americans have quidditch? I thought it was in the UK only. Will they ever join the interscholar turnaments?

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,788

Quidditch? I thought that was fictional.

**In mathematics, you don't understand things. You just get used to them.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,918

It is. You, on the other hand, underestimate the fandom.

*Last edited by anonimnystefy (2012-11-12 12:53:15)*

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,788

Fandom? I love that movie, "Fandom of the Opera!" Emmy Rossum is DDG.

**In mathematics, you don't understand things. You just get used to them.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,918

No, that would be "fantom", not fandom.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,788

You mean phantom. I still like the movie.

**In mathematics, you don't understand things. You just get used to them.**

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