Math

[Megafyr]

Okay, this is a rather strange topic I guess, so I'll start by explaining what it is about.

Today at school we had a task that was like this:

''If you throw a dice twice, what is the change you'll get a seven?''

This is the way I solved it:

The first throw doesn't matter. Whatever number you'll get the second throw determines wheter you get a seven or not.

For example, if you get a one on the first throw, you're gonna have to get a six on the second throw. The chance that you get a six is 1/6=16.7%

I think there is 6/6*1/6=1/6=16.7% chance to get a seven when you throw the dice twice.

My teacher says I'm wrong. She does like this:

first throw 1/6
second throw 1/6

1/6*1/6=1/36=2.78%

(I don't get how she's thinking)

Anyway.. I did a simulation cause I was bored and got these results.

I threw the dice 60*2 times and got a seven exactly 10 times. I know it was a rather short simulation but it ''proves'' that the way I solve it is correct.


Please, help me out! Am I wrong or is my teacher wrong.. If I'm wrong please explain what it is I do wrong and why it is like that, cuz I don't get it : (

Thanks for taking a look at my topic :]

 

[TheDivineBoss]

6| 7 8 9 10 11 12
5| 6 7 8 9 10 11
4| 5 6 7 8 9 10
3| 4 5 6 7 8 9
2| 3 4 5 6 7 8
1| 2 3 4 5 6 7
1 2 3 4 5 6

Go count how many sevens you can find, in this case 6.

6/36 x 100 = 16,67%

I believe it was like this, yeah.

 

[bounty hunter2]

Any number you get the first time, can only be 7 the second time if it is summed with only one number. 6 options. 100 : 6 = 16.67%

 

[Teh_Ephy]

Wow, your teacher sucks at statistics, really. You are doing it perfectly right.

If you are throwing two balls randomly into three buckets, what is the chance that they both land in the same bucket? The initial bucket doesn't matter in the slightest; all that is important is that the second throw is harmonious with the first, so 1/3.

If you said 1/9, you'd be wrong; 1/9 is the chance of both of them landing in a specific bucket. If you add the 1/9 for all three buckets, since which bucket it lands in is unimportant, you have 3/9, or 1/3.

TDB also did it nicely, although I'll fix his diagram for you.

..1..2..3..4..5..6
6|7..8..9.10.11.12
5|6..7..8..9.10.11
4|5..6..7..8..9.10
3|4..5..6..7..8..9
2|3..4..5..6..7..8
1|2..3..4..5..6..7

Each individual outcome (first die 1-6, second die 1-6) is equally likely to occur, correct? That being true, it's possible to calculate the likeliness of possible outcomes by dividing the number of desired outcomes by the number of total possible outcomes.

 

[Megafyr]

Thanks everybody, no I know I'm right

I tried to explain it to my teacher but she still doesn't believe me... Haha x)

 

[Teh_Ephy]

It's because she's thinking about it completely wrong. The chance of a specific outcome of seven, for example the first roll being specifically one and then the second roll being specifically six, is 1/36. The same is true for two and five, three and four, four and three, five and two, and finally six and one. All six of those outcomes have a 1/36 chance of occurring, for a total of 6/36, or 1/6. Try that explanation.

 

[annoying]

I had no idea teachers could be so stupid. All my teachers can admit it if they make mistakes. This Wednesday, we had our Swedish teacher as a substitute in math, and he asked me to help my classmates, because he simply could not.

 

[Megafyr]

It's because she's thinking about it completely wrong. The chance of a specific outcome of seven, for example the first roll being specifically one and then the second roll being specifically six, is 1/36. The same is true for two and five, three and four, four and three, five and two, and finally six and one. All six of those outcomes have a 1/36 chance of occurring, for a total of 6/36, or 1/6. Try that explanation.

Yeah.. If I put it that way she's gotta understand it. Otherwise I'll lose all the respect I got for her in math.. : |

 

[The_wand_mirror]

Thanks everybody, no I know I'm right

I tried to explain it to my teacher but she still doesn't believe me... Haha x)

Guess why.

 

[TheDivineBoss]

Oh the irony, I just watched the Simpsons episode where they said that women can't do math. Off course, to avoid sexism, they 'fixed' it.

 

[Dr Super Good]

Um, are you sure they said a SIX sided dice? Afterall you do get 7 sided or 13 sided or what ever dices for pen and paper RPG games. Thus if it was a 7 sided dice, you would have been wrong but so would she.

Are you sure you are answering the right question? Maybe the question you were asked was different as currently you are right for that question. The question she is answeing is what chance is there for a 12 or 2 to be rolled.

1/6*1/6=1/36=0.03%

She must mean a 2.7778% chance? As your percentage was multiplied by 100, why was hers not?

 

[HINDYhat]

Wow your math teacher fails.

 

[Restor]

well, I made one simple map with triggers that "throws two dices" and if the result was 7, it make one integer variable +1bigger


after 1000times it said that the 7result was in 187times from 1000

thats closer to the 16.7% than 2.7%


well, the second result was 168, thats closer


http://www.sendspace.com/file/7itqrg -you can give this map to your teacher if she is fan of WE :-D

 

[TheDivineBoss]

well, I made one simple map with triggers that "throws two dices" and if the result was 7, it make one integer variable +1bigger


after 1000times it said that the 7result was in 187times from 1000

thats closer to the 16.7% than 2.7%


well, the second result was 168, thats closer


Send big files the easy way. Files too large for email attachments? No problem! -you can give this map to your teacher if she is fan of WE :-D

You played too much Warcraft when:
You give a World Editor file to your teacher that contains the answers made in JASS.

And why does everyone it so hard while you just can make a simple diagram?

Yes I know that simplicity is sometimes wrong, but complexity can be wrong too.

 

[Teh_Ephy]

Um, are you sure they said a SIX sided dice? Afterall you do get 7 sided or 13 sided or what ever dices for pen and paper RPG games. Thus if it was a 7 sided dice, you would have been wrong but so would she.

Are you sure you are answering the right question? Maybe the question you were asked was different as currently you are right for that question. The question she is answeing is what chance is there for a 12 or 2 to be rolled.

She must mean a 2.7778% chance? As your percentage was multiplied by 100, why was hers not?

This is why we all love to hate you, really.

 

[NoobinJass]

Your teacher is fucking stupid!!!
Look:
1+6=7 4+3=7
2+5=7 5+2=7
3+4=7 6+1=7

--> 6 times

So=
6/36 * 100% = 16,7 % (you are right)

 

[Dr Super Good]

This is why we all love to hate you, really.

No one hates me, on the other hand, people certainly hate you now for posting that.

Even if he is right, as long as the teacher says he is wrong he is wrong which is no help if it causes him to fail an exam. He should eithor ask another math teacher who if he supports his argument can tell his teacher she is wrong or should tell his parents who should then complain to the school about teacher incompitence.

If it turns out for some strange reason that even your parents, all maths teachers and everyone believes your way is wrong, then eithor you are surrounded by idiots, or else you answered the wrong question.

 

[En_Fuego]

I find it funny that your math is so inexplicably simple, yet you heil to be the only student in your class to disagree with your teacher.

I have to agree with DSG here. Although it seems you're right, you're probably doing the wrong problem. It's never good to question a teacher's method. It's a lot better to ask another teacher for their take on the situation though!

Also, this is probability (or atleast it looks like it)...
...you don't need to actually do a practice test by throwing the dice
Or by using wc3's magical random number generator..lol

 

[Dr Super Good]

Um, I can question what my math teacher does a lot, as usually he is wrong when I do (he makes quite a few mistakes). Afterall I usually get 100% or slightly less in all the maths tests I am given.

 

[En_Fuego]

You're right. I probably should've said "It's not good to question a teacher's method. Especially if they think they are aryan when it comes to their subject"

 

[PurplePoot]

It isn't good to question a teacher's method? Err... not really. If they're wrong, then you don't get taught wrong. If they're right, then you learn where you went wrong.

 

[TheDivineBoss]

They can have two issues:

Old math / New math

and​

On purpose / Accident

 

[Megafyr]

I'm really sure my teacher is wrong cuz it was that task. Anyway.. Now I got alot of people here on hive supporting me, and alot of people IRL (obviously smart people) supporting me.

I doubt that my teacher stand a chance against me anymore.. Bwahahaha xD

 

[Megafyr]

Um, are you sure they said a SIX sided dice? Afterall you do get 7 sided or 13 sided or what ever dices for pen and paper RPG games. Thus if it was a 7 sided dice, you would have been wrong but so would she.

Are you sure you are answering the right question? Maybe the question you were asked was different as currently you are right for that question. The question she is answeing is what chance is there for a 12 or 2 to be rolled.


She must mean a 2.7778% chance? As your percentage was multiplied by 100, why was hers not?

I forgot it, my mistake : ( 1/36=2.78%

 

[Dr Super Good]

Probably what it is is your maths teacher has a big ego or is unskilled and so can not axcept the fact that she made a mistake.

No one is perfect and mistakes can happen, but as a teacher I would imagine that you would have to axcept that you occasionaly do make mistakes.

You also can not rule out the fact that maybe she sucked at chance and never understood it, in which case she should use a book with correct answers to teach it rather than trying to solve problems herself.

 

[MySpaceBarBroke]

My geometry teacher told me lines were 2 dimensional.

 

[TheDivineBoss]

My geometry teacher told me lines were 2 dimensional.

Give him this.

And yes it has math in it.

 

[Hakeem]

Type the question into Google. Nobody defies Google.

 

[InfiniteSeven]

Nobody defies Google.

I do!

Well only when it comes to the translator. Besides that everything else is fine... or so I think.