• Abcdefghik123 - Monday 18/11/2019, 22:07

Hello! It's time for another giveaway-- whoop whoop!

Your math question for today is
Suzy the Snowman and Douglas are playing tennis. It is currently a deuce (a tie), every ball Suzy has a 1/3 probability of winning and Douglas has a 2/3 probability of winning. The game is won when someone is ahead by more than two points. What is the probability that Suzy wins?

Prizes~
1st Place:

• Bagadur - Tuesday 19/11/2019, 12:46
Colossus - Masters of Battle

19

• Bagadur - Tuesday 19/11/2019, 12:46
Colossus - Masters of Battle

I mean 11.11111%

• klounis - Tuesday 19/11/2019, 13:03
Eternal - Deus eX Machina

1/9

• DUC-KevinAFCA - Tuesday 19/11/2019, 13:33
Moderator - Dutch Urban Crew

1/9 with 2 points in a row at deuce, or 1/27 at Advantage for Douglas. Or 1/3 at Advantage for Suzy
Can't really get a better answer, because the game could go on infinite.
Best answer i can think of is 1/3 on AD Suzy, 1/9 at deuce and 1/27 ot AD Douglas

edited by DUC-KevinAFCA tuesday 19/11/2019, 13:33

• JUGR - Tuesday 19/11/2019, 20:11
Colossus - TRiNiTY

4%

• calitnt - Tuesday 19/11/2019, 21:08
Colossus - Past Present and Future

Its a game, 50% / 50% each side!

So 50%

• Me4e4e - Tuesday 19/11/2019, 21:13
Titan - Harbingers of Ares

32.3333333333333%

• Abcdefghik123 - Wednesday 20/11/2019, 01:08

Oops. I forgot to post the prizes.

The prizes are
1st place: 100K card of choice
2nd place: 50K card of choice
3rd place: 25K card of choice
4th Place: 50 K card of choice
5th Place: 100K card of choice

• Abcdefghik123 - Wednesday 20/11/2019, 01:18

LOL okay. Only 3 ppl have gotten the question right. All of whom DMed, me.

Thus, I will be granting only 3 prizes.
1st Place: 100K+100K=200K card of choice.
2nd Place: 50K+50K=100K card of choice.
3rd Place 25K+25K=50K card of choice.

The winners are the following people:
1st Place: Pere-sonne
2nd Place: FBF_Luis
3rd Place: Manifold

Congratulations! Please dm for the character you want.

For this question, I will offer two solutions.

Solution 1: Let p be the probability that Suzy wins from the deuce position. Then consider two balls after the deuce. Either Suzy has won with probability 1/9, Doug has won with probability 4/9 or it is a deuce again with probability 4/9. Therefore, we can set up this equation: p=1/9+4/9p solving for p we get that Suzy wins with probability 1/5

Solution 2: We can reduce this to the sum of a geometric sequence. Namely the geometric sequence 1/9+4/9*1/9+4/9^2*1/9... The sum of this infinite geometric sequence is (1/9)/(1-4/9)=1/5.

If you have any questions let me know.

abcdefghik123