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**scientia****Member**- Registered: 2009-11-13
- Posts: 222

This is my adaptation of a math problem I came across elsewhere on the Internet.

Mandy has just done her shopping at the shopping center; now she is hungry and wants to go to the restaurant for lunch. Sandy has just had something to eat at the restaurant; now she wants to go to the shopping center and buy some clothes. A park is situated between the shopping center and the restaurant. Mandy sets off from the shopping center at 2:00pm, walks through the park, and arrives at the restaurant at 2:30pm. Sandy leaves the restaurant at 1:43pm, takes the same route through the park (but in the opposite direction) and gets to the shopping center at 2:23pm. Both girls enter the park at the same time and Mandy leaves the park 4 minutes earlier than Sandy.

First question (easy): Find the time (to the nearest minute) at which both girls meet.

*Last edited by scientia (2012-12-29 03:48:24)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

Hi;

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**scientia****Member**- Registered: 2009-11-13
- Posts: 222

Correct.

Next question (harder): At what time did both girls enter the park?

*Last edited by scientia (2012-12-29 03:47:52)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

Hi;

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**scientia****Member**- Registered: 2009-11-13
- Posts: 222

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

Hi;

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**scientia****Member**- Registered: 2009-11-13
- Posts: 222

I'm not sure you you did there. Maybe part of my first post isn't very clear, so I'll try and explain.

The park has two ends, A and B, where A is the end closer to the shopping mall and B the end closer to the restaurant. The route taken by Mandy is: shopping mall → A → park → B → restaurant. Sandy's route is the reverse: restaurant → B → park → A → shopping mall. Thus when I say that the girls enter the park at the same time, I mean that Mandy reaches point A and Sandy reaches point B simultaneously.

*Last edited by scientia (2012-12-29 04:11:47)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

Hi;

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,532

Hi bobbym

I think that should be hidden...

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

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**scientia****Member**- Registered: 2009-11-13
- Posts: 222

*Last edited by scientia (2012-12-29 05:37:50)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

Hi;

Yes, that was a dilly.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**scientia****Member**- Registered: 2009-11-13
- Posts: 222

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

Hi;

A false step on the park size formula. Very good problem.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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