Probability of Getting Red at Least Once in Two Spins of a Wheel with 8 Colors

[pace]

Well approximately it's right because you have all the 3 spins and the probable and possible. But.. ah yes, it doesn't matter of course that you muliply the 8/8 into it because anything muliplied by 1 doesn't change.

 

[pace]

AND you get the possble into it also. Are we sure this is probability and not magic? *laughs*


But shoudn't I as I think, putting it into that / ? So I get the 8/8 at the bottom as the possible

And also I'm maybe a little confused as to how you would get to the answer from the other way around.

 

[tiny-tim]

So.. you'd have to multiply the 'no red x one red' with 'all' to make it a whole division(sp?)

Why I'm really thinking this way I'm not totally sure.

I can tell from the fact you keep writing (and presumably thinking) "one red" and "no red" that you haven't grasped the basics of spinning this wheel.

When you spin the wheel - just once - you get a colour, one colour - it's not like, say, pulling three beads out of a bag.

It's red or yellow or blue or …

But there will only be one colour.

The question is, what is that one colour?

Answer: it's either red or not-red.

Then you spin a second time, and again it's either red or not-red.

So when you describe (1/8)(8/8) + (7/8)(1/8), each of the "/8"s describe the result of one spin.

… possible … probable …

"possible" and "probable" are not words we use in mathematics - they don't mean anything!

Only "probability"!

It's one red x all colours.

You must specify which spin(s) you're talking about.

Try again, specifying the spin.

 

[pace]

I'm not sure how you say in english, but here(norway) it's G/M(gunstige(all the probable(or wanted)/mulige(all the possible outcomes), and use it alot(?) through probability.

 

[tiny-tim]

Yes, we do the same in English, as in "It's probable it will rain" or "It's possible I will win the lottery" - but not in mathematics!

(btw, I'm going out in a few minutes, so if you want another try, you'd better be quick … )

 

[pace]

heh, pulling out balls from a bag was my previous test.
I'm having these sentences in my mind, but they fall out again fast.

I must specify... one red(R) x all(=NN)or:(8/8) , (I have these RN NN things a lot in my mind here, lol) ? hm...

 

[tiny-tim]

heh, pulling out balls from a bag was my previous test.
I'm having these sentences in my mind, but they fall out again fast.

Ah, that explains a lot!

You must get those balls out of your mind, and put them somewhere more appropriate!

I must specify... one red(R) x all(=NN)or:(8/8) , (I have these RN NN things a lot in my mind here, lol) ? hm...

No, it's the-first-spin-is-red-and-the-second-spin-can-be-anything.

Now what is (7/8)(1/8)?

 

[pace]

Riight, I'll get some balls. hehehe.

No I mean.. directly translated it's favorable/those that might happen.

They are strange words to me. Uh. (Edit: Or it's like I see the math and don't see the math. Strange)

 

[pace]

can be anything... wow. (Edit: Yeah well that is I suppose my "those that might happen")

(7/8)(1/8) is first-spin-no-red x second-spin-one-red

 

[pace]

I think I liked can-be-anything definition better.

hm, the 7/8 is a bit confusing to me. I'm abit visual and thinking 7/8 which is 'such a big number' is nothing falls unatural, but this is probably(whaha what a pun) quite normal.

 

[tiny-tim]

(7/8)(1/8) is no red x one red

Well, it's the-first-spin-is-not-red-and-the-second-spin-is-red.

So (1/8)(8/8) + (7/8)(1/8) is the probability of:
the-first-spin-is-red-and-the-second-spin-can-be-anything OR the-first-spin-is-not-red-and-the-second-spin-is-red.

Now, why is that the right answer?

 

[pace]

Good question.

Because we have all the variables? Not enough?! Because..... we have two spins, divided by a +.
First shows the probability-of-one red and probability-of-can-be-everything(uh), the second of probability-of-one-red and probability-of-one-red. We have all the possibilities of at least one red and we're all happy and comfortable.. or.

wow, how did all those sentences come all at once..


But I want the favorable/'can-be-anything' equotation, whaaaa.

 

[tiny-tim]

Nearly there …

Because we have all the variables?

That doesn't mean anything!

The original question was: What is the probability that the outcome will give the colour red at least once.

So we're looking for red-at-least-once.

So why is

red-at-least-once​

the same as

the-first-spin-is-red-and-the-second-spin-can-be-anything OR the-first-spin-is-not-red-and-the-second-spin-is-red?​

 

[pace]

Hm, because ...?

I have to go to work. I'll take little look into it before I reply again! This is fun and helpful.

 

[pace]

No, I was just kidding around when I said just the variables. I always hope I'm good at humour but I'm not.

My thought went as above(in case you haven't seen it):

we have two spins, divided by a +.
First shows the probability-of-one red and probability-of-can-be-everything(uh), the second of probability-of-one-red and probability-of-one-red. We have all the possibilities of at least one red.. Maybe I'm worse at this since it's language and not mathematics

 

[pace]

Or "Red at least once means 3 out of 4 outcomes. the 3 outcomes is defined by 'first spin is red', "third spin is not red", "fourth spin is red", and last as 'can be anything'" (Taking out my favorable/can-be-anything.

uh, something like that? Closer? Grr, I don't like getting math not to work, I get so focused on it.