Saturday

December 20, 2014

December 20, 2014

Posted by **Sam** on Monday, May 31, 2010 at 10:38pm.

Well there are a number of ways for Anna to win like 1st it is 1/6 the second way can be 5/6*1/2*5/6*1/2*1/6 etc. Where do i go from here to find an exact number for the probability?

- Math -
**PsyDAG**, Tuesday, June 1, 2010 at 11:20amWhat happens if Anna rolls the 6 and Bob tosses a head? It it considered a tie, or does one or the other automatically win? This will change the probability of Anna winning the game.

- Math -
**moe**, Saturday, September 11, 2010 at 4:45pmSo, if Ana rolls a 6, does the game end instantly, or does Bob get to flip a coin one last time? If he does, and gets a head, does the game continue or do they declare it a tie?

Does the question really ask for the probability that Ana wins the game, or does it ask for the probability that she wins the game within a certain number of rounds?

On Ana's first roll, she has a 1/6 chance of getting a 6.

In order to get to a second roll, she needs to roll something other than a 6 on her first roll, and Bob needs to get a tails. The probability of that happening is 5/6 * 1/2 = 5/12. Then she has a 1/6 chance of getting a 6 on her 2nd roll, so the probability that Ana wins on her second roll is 5/12*1/6 = 5/72.

probability that she wins on her third roll is 5/6*1/2*5/6*1/2*1/6=25/864

So far, the probability that she wins in three rolls or less is 1/6 + 5/72 + 25/864

This looks like a geometric series, with r=5/12.

Sum of an infinite geometric series is a1/(1-r) where a1= the first term = 1/6

a1/(1-r)=(1/6) / (7/12) = 2/7

**Answer this Question**

**Related Questions**

Math/Probability - Anna and bob play a game in which Anna begins by rolling a ...

Physics - Bob and Bob Jr. stand at open doorways at opposite ends of an airplane...

physics - Bob and Bob Jr. stand at open doorways at opposite ends of an airplane...

Math - At this year's State Fair, there was a dice rolling game. If you rolled ...

Math - The game of dots is played by rolling a fair dice and receiving $1 for ...

Statistics - In a game you roll two fair dice. If the sum of the two numbers ...

Math-Fair Game question - the game of dots is played by rolling a fair die and ...

math fair - The game of dots is played by rolling a fair die and receiving $1 ...

math stuff - suppose to arrage the names of the ppl in descending order of their...

math - In rolling a pair of dice, suppose you win $5 if the sum is 10 but lose $...