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rwsaunders
08-16-2007, 10:55 PM
Just getting the kids back into math for the school season. Any good stumpers out there?

dave thompson
08-16-2007, 11:07 PM
Just getting the kids back into math for the school season. Any good stumpers out there?
Yes. How many bikes does it take to find the 'perfect' one?

DarrenCT
08-16-2007, 11:13 PM
how many beers in a case of beer?

DarrenCT
08-16-2007, 11:13 PM
Yes. How many bikes does it take to find the 'perfect' one?

at least 5

markie
08-16-2007, 11:34 PM
What is the perfect # of bikes?

Ahneida Ride
08-17-2007, 12:21 AM
Why would anyone major in Mathematics when you can make a ton
of frn doing just about anything else?

Kahuna
08-17-2007, 12:26 AM
rw,

I enjoy solving these whenever I get bored watching reruns of "Married with Children"....

Bud_E
08-17-2007, 12:37 AM
rw,

I enjoy solving these whenever I get bored watching reruns of "Married with Children"....


If you solve it, you will know how many angels can dance on the head of a pin.

Ahneida Ride
08-17-2007, 01:50 AM
rw,

I enjoy solving these whenever I get bored watching reruns of "Married with Children"....

Not as bad as 3 dimensional Navier-Stokes

TimB
08-17-2007, 09:35 AM
42

And _I_ majored in mathematics, twice.

gt6267a
08-17-2007, 09:49 AM
what grade / level are the kids?

when lost, i always answered 0, 1, or 3.14. there is nothing like answering 3.14 when the problem has not even the faintest rumor of having to do with pie. it was always good for a few points and a LOL. thankfully, i did not need to pull that one out very often.

Tom
08-17-2007, 09:54 AM
Why would anyone major in Mathematics when you can make a ton
of frn doing just about anything else?

I wish to hell I had majored in math. I'm a dumb mainframe systems tech and everything cool I ever see in this field has some very serious math behind it and I wish to hell I understood it because then I'd get to do the cool stuff.

Everything has math behind it.

Math is the only science that requires proof.

I'm going to screw up this joke:

A biologist, a physicist and a mathemetician are on a train. It passes a field full of livestock. The biologist looks up and says "A field of sheep." The physicist looks up and says "Yeah, and one's a black sheep." The mathemetician looks up and says "It is a field containing a set of sheep, exactly one half of one of which is black."

Math is tough, though. One of the smartest people I know, (double strand RNA, anyone?) switched his major at MIT from physics when he realized he, in his words, simply didn't have the math chops. Considering he's one of the first two or three people to have figured out what micro RNA does, it gives me a lot of respect for people that can do proofs.

BURCH
08-17-2007, 10:00 AM
rw,

I enjoy solving these whenever I get bored watching reruns of "Married with Children"....


Ahhh!! I am having flashbacks to Physical Chemistry and the Calc that it required. Thank goodness for Extra Credit and MathCad software.

Ahneida Ride
08-17-2007, 10:15 AM
Math is tough, though.

Spent two summers living like a monk to pass the qualifiers.
Fluked twice. Finally passed on the third attempt.

You are no dummy Tom.

Michael Maddox
08-17-2007, 10:17 AM
I wish to hell I had majored in math. I'm a dumb mainframe systems tech and everything cool I ever see in this field has some very serious math behind it and I wish to hell I understood it because then I'd get to do the cool stuff.

Everything has math behind it.

Math is the only science that requires proof.

I'm going to screw up this joke:

A biologist, a physicist and a mathemetician are on a train. It passes a field full of livestock. The biologist looks up and says "A field of sheep." The physicist looks up and says "Yeah, and one's a black sheep." The mathemetician looks up and says "It is a field containing a set of sheep, exactly one half of one of which is black."

Math is tough, though. One of the smartest people I know, (double strand RNA, anyone?) switched his major at MIT from physics when he realized he, in his words, simply didn't have the math chops. Considering he's one of the first two or three people to have figured out what micro RNA does, it gives me a lot of respect for people that can do proofs.

It's not too late. I'm 38 and in Mathematics at FSU. After years of software development, I decided that what I really needed was a new perspective on problem solving. Rigorous proof requires insight and creativity that REALLY gets your cogs spinning. It's simply one of the best ways to exercise your brain. With some background in fine art and strong writing skills, I feel like I'm completing a trifecta of some sort. My ideas about the holistic nature of knowledge are finally beginning to gel.

Teaching the "wow!" parts of math to my kids (9, 6, and 3 years old) is a lot of fun, too.

Give me a bit, and I'll post some good ones.

BURCH
08-17-2007, 10:25 AM
Rigorous proof requires insight and creativity that REALLY gets your cogs spinning. It's simply one of the best ways to exercise your brain.


I absolutely agree with this. I would always walk away from proof work exhausted. Somehow both physically and mentally exhausted. I have yet to match this exhaustion since graduating because i don't need to work with proofs anymore. Sorta sad, but I don't miss that aspect of science.

pjm
08-17-2007, 10:49 AM
Ask Winnie Cooper. Really.
http://en.wikipedia.org/wiki/Danica_McKellar

Ahneida Ride
08-17-2007, 10:55 AM
I love Proofs, It's how I think and live.
I tear everytihg apart and reassemble.
This makes me look real stupid at times. ( at times? :eek: )
I focus in on definitions. very important.

Took me over 1 year to figure frnacation and fictional reserve banking.
because it does not make sense. Defies evey mathematical convention
I've learned.

The I realized, It is not supposed to make sense. Just generate tons of
frn for an elite privileged few at the expense of diluting the rest of us with
escalating prices and enslaving debt.

fiamme red
08-17-2007, 11:00 AM
Took me over 1 year to figure frnacation and fictional reserve banking. because it does not make sense. Defies evey mathematical convention I've learned.

The I realized, It is not supposed to make sense. Just generate tons of frn for an elite privileged few at the expense of diluting the rest of us with escalating prices and enslaving debt.Aren't you violating the terms of your double secret probation? :no: :rolleyes: ;)

znfdl
08-17-2007, 11:53 AM
Chocolate Math:

1. First of all, pick the number of times a week that you would like to have chocolate (more than once but, less than 10).
2. Multiply this number by 2 (Just to be bold)
3. Add 5 additional pieces for Sunday.
4. Multiply the sum by 50.
5. If you have already had your birthday this year add 1755 to the sum. If you haven't, add 1754 to the sum
6. Now subtract the four digit year that you were born (note: You should have a three digit number).
7. The first digit of this was your original number (i.e. how many times you want to have chocolate each week).
8. The next two numbers are YOUR AGE!

9. Note this math problem only works for the year 2005.

Function:
Let x = chocolate
f(chocolate)= (2x + 5)*50 + 1755 1995
f(chocolate)= 100x + 250 + 1755 1995 (note; 250+1755-1995 resolves to age)
f(chocolate) = 100x + 10

Note for a generic formula for any future year:
f(chocolate)= (2*(chocolate) + 5)*50 + (1754/1755 + (current year 2005)) Year Born

Also, if you would like for me to talk a little about probability and if you have discussed Pi, I have some interesting elementary examples of probability to calculate Pi. Additionally, this could be used as a backdoor way to describe Pi.

A simple example would be to super impose a circle on a square which has a side length of 1. Therefore, the diameter of the circle would also be 1.

Assume that the circle is shaded and the square is not. Now if random pair of numbers were selected for the x and y coordinates, it could be determined if the random pair of coordinates fall within the circle. For class interaction, let the class pick some random number pairs, while I could have several thousand pairs of random numbers on a spreadsheet.

If enough random pairs of coordinates were picked it would show that:

Pi = (number of coordinates falling within the shaded area / number of coordinates that fall in the square).

This can also be represented by a dart board on a square piece of cork.

sspielman
08-17-2007, 11:56 AM
Fifty Years of Math 1957 - 2007
>
>
>
> Last week I purchased a burger at Burger King for $1.58. The counter girl took my $2 and I was digging for my change when I pulled 8 cents from my pocket and gave it to her. She stood there, holding the nickel and 3 pennies, while looking at the screen on her register. I sensed her discomfort and tried to tell her to just give me two quarters, but she hailed the manager for help. While he tried to explain the transaction to her, she stood there and cried. Why do I tell you this?
>
> Because of the evolution in teaching math since the 1950s:
>
> 1. Teaching Math In 1950s
>
> A logger sells a truckload of lumber for $100. His cost of production is 4/5 of the price. What is his profit ?
>
> 2. Teaching Math In 1960s
>
> A logger sells a truckload of lumber for $100 His cost of production is 4/5 of the price, or $80. What is his profit?
>
> 3. Teaching Math In 1970s
>
> A logger sells a truckload of lumber for $100. His cost of production is $80. Did he make a profit?
>
> 4. Teaching Math In 1980s
>
> A logger sells a truckload of lumber for $100. His cost of production is $80 and his profit is $20. Your assignment: Underline the number 20.
>
> 5. Teaching Math In 1990s
>
> A logger cuts down a beautiful forest because he is selfish and inconsiderate and cares nothing for the habitat of animals or the preservation of our woodlands. He does this so he can make a profit of $20. What do you think of this way of making a living? Topic for class participation after answering the question: How did the birds and squirrels feel as the logger cut down their homes? (There are no wrong answers, and if you feel like crying, it's OK. )
>
> 6. Teaching Math In 2007
>
> Un hachero vende una carretada de madera para $100. El costo de la producciones es $80. Cuanto dinero ha hecho?

Ahneida Ride
08-17-2007, 12:15 PM
Aren't you violating the terms of your double secret probation? :no: :rolleyes: ;)

Probably yes. Time for triple esoteric isolation? ;)
I'm still waiting for the PM from an administrator to tell me cool it.

Frnacation and fictional reserve banking are so secret that not
one in 10,000 understand it.

Why is it not the basis of our financial engine taught in schools?
frns are create outa thin air. We pay interest on em. Banks allow
multiple claims to the same frn.

I can tell you. Because this is just too dangerous a secret to reveal.
It's absurdity must be kept confidential.
One must never discover the true cause of higher and higher prices.

Ozz
08-17-2007, 12:23 PM
Yes. How many bikes does it take to find the 'perfect' one?
....please see "infinite monkey theorem" (http://www.monkeyswithtypewriters.net/)

mosca
08-17-2007, 12:25 PM
Math not so hard...

Ahneida Ride
08-17-2007, 12:27 PM
sspielman ...

It is far worse then you think .... Far far worse.

At a leading academic institution, The PhD prelim exams have gone
from Graduate level mathematics to advanced undergraduate math
to now glorified Freshman Calculus.
Students still have problems passing em.

PhD course work has gone from 4 years to 3 years.

Foreign language requirement has gone from 2 languages to none.

This nation has a real problem. The facts speak for themselves.
Throwing even more Trillions into education is not the solution.

----------------------------


Fifty Years of Math 1957 - 2007
>
>
>
> Last week I purchased a burger at Burger King for $1.58. The counter girl took my $2 and I was digging for my change when I pulled 8 cents from my pocket and gave it to her. She stood there, holding the nickel and 3 pennies, while looking at the screen on her register. I sensed her discomfort and tried to tell her to just give me two quarters, but she hailed the manager for help. While he tried to explain the transaction to her, she stood there and cried. Why do I tell you this?
>
> Because of the evolution in teaching math since the 1950s:
>
> 1. Teaching Math In 1950s
>
> A logger sells a truckload of lumber for $100. His cost of production is 4/5 of the price. What is his profit ?
>
> 2. Teaching Math In 1960s
>
> A logger sells a truckload of lumber for $100 His cost of production is 4/5 of the price, or $80. What is his profit?
>
> 3. Teaching Math In 1970s
>
> A logger sells a truckload of lumber for $100. His cost of production is $80. Did he make a profit?
>
> 4. Teaching Math In 1980s
>
> A logger sells a truckload of lumber for $100. His cost of production is $80 and his profit is $20. Your assignment: Underline the number 20.
>
> 5. Teaching Math In 1990s
>
> A logger cuts down a beautiful forest because he is selfish and inconsiderate and cares nothing for the habitat of animals or the preservation of our woodlands. He does this so he can make a profit of $20. What do you think of this way of making a living? Topic for class participation after answering the question: How did the birds and squirrels feel as the logger cut down their homes? (There are no wrong answers, and if you feel like crying, it's OK. )
>
> 6. Teaching Math In 2007
>
> Un hachero vende una carretada de madera para $100. El costo de la producciones es $80. Cuanto dinero ha hecho?

Chief
08-17-2007, 12:58 PM
Fifty Years of Math 1957 - 2007
>
>
>
> Last week I purchased a burger at Burger King for $1.58. The counter girl took my $2 and I was digging for my change when I pulled 8 cents from my pocket and gave it to her. She stood there, holding the nickel and 3 pennies, while looking at the screen on her register. I sensed her discomfort and tried to tell her to just give me two quarters, but she hailed the manager for help. While he tried to explain the transaction to her, she stood there and cried. Why do I tell you this?
>
> Because of the evolution in teaching math since the 1950s:
>
> 1. Teaching Math In 1950s
>
> A logger sells a truckload of lumber for $100. His cost of production is 4/5 of the price. What is his profit ?
>
> 2. Teaching Math In 1960s
>
> A logger sells a truckload of lumber for $100 His cost of production is 4/5 of the price, or $80. What is his profit?
>
> 3. Teaching Math In 1970s
>
> A logger sells a truckload of lumber for $100. His cost of production is $80. Did he make a profit?
>
> 4. Teaching Math In 1980s
>
> A logger sells a truckload of lumber for $100. His cost of production is $80 and his profit is $20. Your assignment: Underline the number 20.
>
> 5. Teaching Math In 1990s
>
> A logger cuts down a beautiful forest because he is selfish and inconsiderate and cares nothing for the habitat of animals or the preservation of our woodlands. He does this so he can make a profit of $20. What do you think of this way of making a living? Topic for class participation after answering the question: How did the birds and squirrels feel as the logger cut down their homes? (There are no wrong answers, and if you feel like crying, it's OK. )
>
> 6. Teaching Math In 2007
>
> Un hachero vende una carretada de madera para $100. El costo de la producciones es $80. Cuanto dinero ha hecho?

I recall being in a fast food resturant for lunch and the guy ahead of me placed his order and paid for it. He was to get back about 80 cents in change and which was counted out in nickels. He walked away with a fist full of nickels shaking his head. Forunately, for me my change was only 20 cents.

Louis
08-17-2007, 01:20 PM
Math is the only science that requires proof.

Been reading stuff taught in the Kansas school districts?

rounder
08-18-2007, 12:11 AM
Fifty Years of Math 1957 - 2007
>
>
>
> Last week I purchased a burger at Burger King for $1.58. The counter girl took my $2 and I was digging for my change when I pulled 8 cents from my pocket and gave it to her. She stood there, holding the nickel and 3 pennies, while looking at the screen on her register. I sensed her discomfort and tried to tell her to just give me two quarters, but she hailed the manager for help. While he tried to explain the transaction to her, she stood there and cried. Why do I tell you this?
>
> Because of the evolution in teaching math since the 1950s:
>
> 1. Teaching Math In 1950s
>
> A logger sells a truckload of lumber for $100. His cost of production is 4/5 of the price. What is his profit ?
>
> 2. Teaching Math In 1960s
>
> A logger sells a truckload of lumber for $100 His cost of production is 4/5 of the price, or $80. What is his profit?
>
> 3. Teaching Math In 1970s
>
> A logger sells a truckload of lumber for $100. His cost of production is $80. Did he make a profit?
>
> 4. Teaching Math In 1980s
>
> A logger sells a truckload of lumber for $100. His cost of production is $80 and his profit is $20. Your assignment: Underline the number 20.
>
> 5. Teaching Math In 1990s
>
> A logger cuts down a beautiful forest because he is selfish and inconsiderate and cares nothing for the habitat of animals or the preservation of our woodlands. He does this so he can make a profit of $20. What do you think of this way of making a living? Topic for class participation after answering the question: How did the birds and squirrels feel as the logger cut down their homes? (There are no wrong answers, and if you feel like crying, it's OK. )
>
> 6. Teaching Math In 2007
>
> Un hachero vende una carretada de madera para $100. El costo de la producciones es $80. Cuanto dinero ha hecho?


Yeah - that sums it up.

Sandy
08-18-2007, 12:19 AM
Fifty Years of Math 1957 - 2007
>
>
>
> Last week I purchased a burger at Burger King for $1.58. The counter girl took my $2 and I was digging for my change when I pulled 8 cents from my pocket and gave it to her. She stood there, holding the nickel and 3 pennies, while looking at the screen on her register. I sensed her discomfort and tried to tell her to just give me two quarters, but she hailed the manager for help. While he tried to explain the transaction to her, she stood there and cried. Why do I tell you this?
>
> Because of the evolution in teaching math since the 1950s:
>
> 1. Teaching Math In 1950s
>
> A logger sells a truckload of lumber for $100. His cost of production is 4/5 of the price. What is his profit ?
>
> 2. Teaching Math In 1960s
>
> A logger sells a truckload of lumber for $100 His cost of production is 4/5 of the price, or $80. What is his profit?
>
> 3. Teaching Math In 1970s
>
> A logger sells a truckload of lumber for $100. His cost of production is $80. Did he make a profit?
>
> 4. Teaching Math In 1980s
>
> A logger sells a truckload of lumber for $100. His cost of production is $80 and his profit is $20. Your assignment: Underline the number 20.
>
> 5. Teaching Math In 1990s
>
> A logger cuts down a beautiful forest because he is selfish and inconsiderate and cares nothing for the habitat of animals or the preservation of our woodlands. He does this so he can make a profit of $20. What do you think of this way of making a living? Topic for class participation after answering the question: How did the birds and squirrels feel as the logger cut down their homes? (There are no wrong answers, and if you feel like crying, it's OK. )
>
> 6. Teaching Math In 2007
>
> Un hachero vende una carretada de madera para $100. El costo de la producciones es $80. Cuanto dinero ha hecho?


Priceless!!! I enjoyed that. I was a high school math teacher many moons ago. Loved the kids, enjoyed the teaching, but the school administration and I did not mesh so well. But they basically left me alone most of the time, especially in the classroom.


Sandy

Elefantino
08-18-2007, 12:43 AM
What is the perfect # of bikes?
Too easy.

N + 1

Ahneida Ride
08-18-2007, 12:46 AM
Too easy.

N + 1

Good one ....

Now Iterate ....

11.4
08-18-2007, 11:49 AM
It isn't really for kids, but there's a superb book out there: "It Must be Beautiful: Great Equations of Modern Science," edited by Graham Farmelo. It's chapters, each on a major mathematical advance in science (Schrodinger equation, Yang-Mills, Planck-Einstein, Einstein Relativity, etc.) are written by applied mathematicians such as John Maynard Smith, Robert May, Christine Sutton, Steven Weinberg, Roger Penrose, etc. Each chapter describes the origins of the equation and its context in the creative environment plus scientific interest at the time, and goes on to explain just why it's great and why "beautiful" is not an inappropriate adjective.

As a mathematician turned physical chemist turned molecular biologist, it draws out the aesthetic interest in the field that mathematicians tend to understand but is so hard to convey to students. The read is a bit much for a high school student but an adult can read the book and convey the appreciation of the work to children.

rounder
08-18-2007, 11:45 PM
why pii...how did they come up with that??

Louis
08-19-2007, 12:06 AM
A simple example would be to super impose a circle on a square which has a side length of 1. Therefore, the diameter of the circle would also be 1.

Assume that the circle is shaded and the square is not. Now if random pair of numbers were selected for the x and y coordinates, it could be determined if the random pair of coordinates fall within the circle. For class interaction, let the class pick some random number pairs, while I could have several thousand pairs of random numbers on a spreadsheet.

If enough random pairs of coordinates were picked it would show that:

Pi = (number of coordinates falling within the shaded area / number of coordinates that fall in the square).

Z,

I've done this using random number generators (say in Excel or MATLAB) and it is fun, but to get close one has to "throw" quite a few darts.

Another interesting way of deriving pi is to inscribe a polygon in a circle (one can also put the circle in the polygon, both methods are essentially similar) and calculating the periphery of the polygon. As the polygon gets more and more sides it will approximate the circle. Since it's very easy to calculate the ratio of the "radius" of the polygon to the periphery one can find an approximation to pi. This is a powerful method and it doesn't take long to get very close. Plus, it converges much faster than the "dartboard" method...

Louis

znfdl
08-19-2007, 12:39 PM
Louis:

Thanks for the tip.

deanster
08-19-2007, 11:14 PM
at least 5

Sorry...Wrong! Always one more than you have.

deanster
08-19-2007, 11:15 PM
Good one ....

Now Iterate ....

Agree absolutely!