binomial probability-tennis quest (1 Viewer)

[mwseaeagles]

martina beats jelena in 2 games out of 3 at tennis. what is the probability that jelena wins a set of tennis 6 games to 4.

the answer is 0.0341 but yeh i cant get any progress at all

cheerz

 

[lyounamu]

martina beats jelena in 2 games out of 3 at tennis. what is the probability that jelena wins a set of tennis 6 games to 4.

the answer is 0.0341 but yeh i cant get any progress at all

cheerz

My interpretation: Let P(Jelena Losing) = P(X) = 2/3
Let Q(Jelena Winning) = P(Q) = 1/3

P(6 wins and 4 losses) = 10C4 . 1/3^6 . 2/3^4 = 0.05690189950...

I am not sure if your answer is right...

Is that the full question you posted up? I think there might be some problems with the wording. Please post the FULL QUESTION (with accurate wording). I interpreted that Jelena wins 6 times and 4 times in a set (not taking account of the number of games or anything).

2nd interpretation:

Let P(Jelena Losing) = 2/3
Let Q(Jelena Winning) = 1/3

Since the score is 2-1 to Martina way. So Jelena must win 5 games and lose two.

P(Winnig 5 games and lose two) = 7C2 . 1.3^5 . 2/3^2 = 0.0384097791...

 

[bored of sc]

Haven't done this topic yet but here's the information I got out of the question.

martina beats jelena in 2 games out of 3 at tennis:
The score is 2-1 in the first set; Martina over Jelena.

what is the probability that jelena wins a set of tennis 6 games to 4:
The possible scores for the first set could be:
7-6 to Martina.
7-5 to Martina.
6-4 to Martina.
6-3 to Martina.
6-2 to Martina.
6-1 to Martina.
7-6 to Jelena.
7-5 to Jelena.
6-4 to Jelena.
6-3 to Jelena.
6-2 to Jelena.

That's all I know, if that even helped the slightest.

 

[lyounamu]

Haven't done this topic yet but here's the information I got out of the question.

martina beats jelena in 2 games out of 3 at tennis:
The score is 2-1 in the first set; Martina over Jelena.

what is the probability that jelena wins a set of tennis 6 games to 4:
The possible scores for the first set could be:
7-6 to Martina.
7-5 to Martina.
6-4 to Martina.
6-3 to Martina.
6-2 to Martina.
6-1 to Martina.
7-6 to Jelena.
7-5 to Jelena.
6-4 to Jelena.
6-3 to Jelena.
6-2 to Jelena.

That's all I know, if that even helped the slightest.

So you interpreted the question in a different way. Um...

 

[bored of sc]

So you interpreted the question in a different way. Um...

I bet YOU got the right way though.

I would've said 1/11 = 0.0909090909090909090909090909...

 

[jake2.0]

But the question asks

what is the probability that jelena wins a set of tennis 6 games to 4.

rather than "whats the probability that jelena wins this set of tennis."

So I think lyounamu's way is correct

 

[lyounamu]

I bet YOU got the right way though.

I would've said 1/11 = 0.0909090909090909090909090909...

I wouldn't be surprised if you got it right because the wording was confusing.

 

[Aerath]

Why is it that the names are actual names of real tennis players?
Martina Hingis/Navratilova
Jelena Jankovic

 

[mwseaeagles]

I wouldn't be surprised if you got it right because the wording was confusing.

nah its the whole thing

 

[lyounamu]

nah its the whole thing

And the answer you posted up is right?

 

[eyetalian]

LOL!

its Martina Hingis and Jelena Dokic, not Jankovic.

Dokic beat Hingis in the first round of wimbledon in 1999, Hingis only won 2 games in the match and was the number 1 seed at the event.

 

[Aerath]

Meh, oh well.
I haven't heard about Jelena Dokic in ages. I think most people remember her father more than they remember her.

 

[Trebla]

The key thing you have to realise is that once one person hits the 6 games won, then the set is over. In other words say if Jelena is at 6 and Martina is at 3, there's no way Martina can get up to 4, it's already over. So Jelena must win the last game. You must account for that in the calculations.

So interpret this as the probability that Jelena get's 5 and Martina gets 4 games, because they can be in any order.
P(J = 5, M = 4) = ⁹C₅(1/3)⁵(2/3)⁴
But Jelena MUST win the last game, so the probability we get 6 games for Jelena and 4 games for Martina (i.e. with Jelena winning) is:
(1/3) x P(J = 5, M = 4) = (1/3) x ⁹C₅(1/3)⁵(2/3)⁴ ~ 0.0341

 

[mwseaeagles]

The key thing you have to realise is that once one person hits the 6 games won, then the set is over. In other words say if Jelena is at 6 and Martina is at 3, there's no way Martina can get up to 4, it's already over. So Jelena must win the last game. You must account for that in the calculations.

So interpret this as the probability that Jelena get's 5 and Martina gets 4 games, because they can be in any order.
P(J = 5, M = 4) = ⁹C₅(1/3)⁵(2/3)⁴
But Jelena MUST win the last game, so the probability we get 6 games for Jelena and 4 games for Martina (i.e. with Jelena winning) is:
(1/3) x P(J = 5, M = 4) = (1/3) x ⁹C₅(1/3)⁵(2/3)⁴ ~ 0.0341

man that was good. thanks so much

 

[lyounamu]

The key thing you have to realise is that once one person hits the 6 games won, then the set is over. In other words say if Jelena is at 6 and Martina is at 3, there's no way Martina can get up to 4, it's already over. So Jelena must win the last game. You must account for that in the calculations.

So interpret this as the probability that Jelena get's 5 and Martina gets 4 games, because they can be in any order.
P(J = 5, M = 4) = ⁹C₅(1/3)⁵(2/3)⁴
But Jelena MUST win the last game, so the probability we get 6 games for Jelena and 4 games for Martina (i.e. with Jelena winning) is:
(1/3) x P(J = 5, M = 4) = (1/3) x ⁹C₅(1/3)⁵(2/3)⁴ ~ 0.0341

That's ridiculous. I mean, how were we supposed to take that thing into account. What if people don't know about tennis?

But good work. That's was a extremely well done.

 

[Trebla]

That's ridiculous. I mean, how were we supposed to take that thing into account. What if people don't know about tennis?

Well, how else would Jelena be declared the winner? lol. Though I do somewhat agree, it should say that the first person to take 6 games wins.