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#1 Re: Computer Math » Self Avoiding Walk » Yesterday 12:51:26

Thank You. Will look into that

#3 Re: Dark Discussions at Cafe Infinity » Princeton, Harvard and MIT? » Yesterday 05:21:06

Biological Thermodynamics wrote:

This equation might look abstract and confusing.

Why were you surfing 9GAG?

#5 Re: Help Me ! » Coins - Expectancy » 2014-10-19 02:48:33

New Problem Statistics-

14 views (100%)   8 attempts (57%)   2 solvers (14%)

(so far)

#7 Re: Help Me ! » Coins - Expectancy » 2014-10-18 22:38:58

bobbym wrote:

Each additional answer lowers the value of mine. It was already less than 100 when I answered it.

It does not affect your score once you answer it.

I did not think it should be of value > 100

There is a subtle difference between that question and this one. See the last line of the question.

#8 Re: Help Me ! » Coins - Expectancy » 2014-10-18 12:30:32

The question is original. So, I have the right to post it anywhere.

I cannot change it to a link because the question is not available elsewhere.

#9 Euler Avenue » Grant Wiggins Challenge » 2014-10-18 05:17:42

Replies: 0

1) “You can’t divide by zero.” Explain why not, (even though, of course, you can multiply by zero.)

2) “Solving problems typically requires finding equivalent statements that simplify the problem” Explain – and in so doing, define the meaning of the = sign.

3) You are told to “invert and multiply” to solve division problems with fractions. But why does it work? Prove it.

4) Place these numbers in order of largest to smallest: .00156, 1/60, .0015, .001, .002

5) “Multiplication is just repeated addition.” Explain why this statement is false, giving examples.

6) A catering company rents out tables for big parties. 8 people can sit around a table. A school is giving a party for parents, siblings, students and teachers. The guest list totals 243. How many tables should the school rent?

7) Most teachers assign final grades by using the mathematical mean (the “average”) to determine them. Give at least 2 reasons why the mean may not be the best measure of achievement by explaining what the mean hides.

8) Construct a mathematical equation that describes the mathematical relationship between feet and yards. HINT: all you need as parts of the equation are F, Y, =, and 3.

9) As you know, PEMDAS is shorthand for the order of operations for evaluating complex expressions (Parentheses, then Exponents, etc.). The order of operations is a convention. X(A + B) = XA + XB is the distributive property. It is a law. What is the difference between a convention and a law, then? Give another example of each.

10) Why were imaginary numbers invented? [EXTRA CREDIT for 12th graders: Why was the calculus invented?]

11) What’s the difference between an “accurate” answer and “an appropriately precise” answer? (HINT: when is the answer on your calculator inappropriate?)

12) True or false: .99999.... = 1

13) Explain why a negative times a negative is a positive.

#10 Help Me ! » Coins - Expectancy » 2014-10-17 18:09:32

Replies: 9

A Kaboobly Dooist discovers an infinite pool of coins with $1, $2 and $5 coins distributed uniformly in it. He takes a coin at random from the pool and puts it in his bag. He does so until the sum of the values of all coins in his bag is equal to or more than $200.

If the expected number of $1 coins is n, what is the value of floor(10*n)?

#12 Re: Jokes » Math Pick-up Lines » 2014-10-17 12:26:05

Do not glance that way,
it'd make me a bumpkin
I loose the way of my eyes
my heart shakes
Struck by the situation-
-I am waiting like an idiot since then.
With the teacup in your hands
you toy with me.
With Crickets chirping in my knees,
Concious I am no more
And I have no idea when it started raining
[Do not drench yourself in the rain,
You'll catch cold
are you crazy?](2)
[what would happen to me?] (2)
[A lost life, an absent mind-
How tempting your eyes are, dear?
Only a desert, in my life prevails.
O colorful, you never come to realise?](2)
[Do not wear glasses
they'll cover your eyes!
are you crazy?
[What'd happen to me?] (2)
[Just like a living corpse- melancholic, I am
Filling my head with stuff about you.
What sort of a girl are you, you never think about it?
And vanish into your own room!] (2)
[Do not pull the curtains
it'll bring darkness!
Are you crazy?](2)
[What'd happen to me?](6)

#15 Re: Help Me ! » Trigonometric Equations » 2014-10-13 02:34:34

Solve: cos(x) - sin(3x) = cos(2x)

#16 Re: Help Me ! » Maximise ... » 2014-10-10 01:24:37

In the library in the sky, to which pappym had access? I will see what I can do?

#17 Re: Help Me ! » Maximise ... » 2014-10-10 01:11:59

Never even heard of it

#20 Re: Help Me ! » Maximise ... » 2014-10-09 20:41:39

How can I do this with a language that does not have built in functions like NMaximize

#21 Re: Help Me ! » Maximise ... » 2014-10-09 20:00:06

What good is the analytical answer?

#22 Re: Help Me ! » Maximise ... » 2014-10-09 19:51:54


Can you tell me how to code up that fucntion myself?

#24 Re: Help Me ! » Maximise ... » 2014-10-09 19:23:35

What is the algorithm?

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