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**n872yt3r****Member**- Registered: 2013-01-21
- Posts: 392

There is an awesome challenge online. Since yesterday was pi day (March 14) they have something really cool.

www.pidaychallenge.com

3.14159265358979... Ok.

It's a series of levels where you have to answer lots of math questions.

Here are some of the questions below:

1. Name the first 5 decimal digits of pi.

3. (This is a trick question) What does the license plate say?

6A. The ___________ Theorem states that for any right triangle, the sum of the lengths equals the square of the length of the hypotenuse.

6B. What is x?

9. What are the roots of the function

11. What is Archimedes' ratio approximation of pi?

I'm completely stuck on #23:

You run downwards at a speed of 3 steps per second.

It takes you 180 steps to get to the bottom.

You walk upwards at a speed of 1 step per second.

It takes you 20 steps to get to the top.

How many steps do you need if the escalator stands still?

*Last edited by n872yt3r (2013-03-16 23:02:19)*

- n872yt3r

Math Is Fun Rocks!

By the power of the exponent, I square and cube you!

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Happy Pi Day and Thanks for the link

Is that the full statement of the problem?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**n872yt3r****Member**- Registered: 2013-01-21
- Posts: 392

It's all they tell me. There's another incomplete question. You have to find the area of the blue shaded area of a triangle with 10 equally tangent circles inside, but you can see the side **or** the radius.

- n872yt3r

Math Is Fun Rocks!

By the power of the exponent, I square and cube you!

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I am also struck at that equilateral

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**digits****Member**- Registered: 2013-01-02
- Posts: 6

Oh!

I forgot to wish everybody Happy Pi Day on March 14th!

Hope it was good for you all.

Cheers! digits

Bring me my Bow of burning Gold!

Bring me my Arrows of Desire!

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Answer: 60 steps

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,691

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

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My father helped me

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,691

Looks like I needed the help...

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

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**n872yt3r****Member**- Registered: 2013-01-21
- Posts: 392

Thanks guys now I'm on 26; it's not an actual problem but a visual logic puzzle.

- n872yt3r

Math Is Fun Rocks!

By the power of the exponent, I square and cube you!

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Hi bobbym,

Can you walk me out through problem 22

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,691

Problem 22? I do not know it?!

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

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There are 10 circles each of radius 3 cm stacked like this:

*

* *

* * *

* * * *

Then they are being inscribed by a triangle. Something like this, but more tightly, I mean perfectly inscribing:

^

/ * \

/ * * \

/ * * * \

/ * * * * \

________

What is the area of that triangle?

The person below enjoyed that ASCII art

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,691

How close must the answer be and what type of answer?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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That is not important. I only want to know how it is done

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,691

An analytical solution is different than a numerical one. Do you need a closed form?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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What is a closed form? I would say an analytical one because the radii of the circle may be different

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,691

An expression is said to be a closed-form expression if it can be expressed in terms of a finite number of elementary expressions.

is in closed form

is not.

Both represent numbers but the integral is not an elementary function.

Perhaps a better question is, do you want an exact answer?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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no, I want to know how the question can be attacked

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,691

Numerically will yield an answer quickly. Then the only question is one of accuracy.

For instance the triangles area is approximately 350 cm.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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Numerically will yield an answer quickly. Then the only question is one of accuracy.

I do not want the answer badly. I've already cracked the answer by intellignet brute-force

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,691

Then I am interested in what you did.

I would do it in one of two ways. Use geogebra to make a very fine diagram and extrapolate to the answer by making several ansatzes.

I would place the circles one using simultaneous equations and then figure the triangle that would enclose them. It will require M.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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That puzzle had an option, either you can ask for the length of the sides of the triangles or the radii of the circles.

Unfortunately, each time I refreshed the page, the problem was regenerated with new values

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,691

I also would first investigate all the literature.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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Using what kind of a search algorithm?

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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