







Amy is playing a game 
20070825 

From vanessa: problem statement:
amy is playing a game.
in order to win this game, she has to draw a redcoloured card from a given box.
advise her on her chances of winning. Answered by Penny Nom. 





Combining probabilities 
20070820 

From Arul: Xavier, Yvonne, and Zelda each try independently to solve a problem. If their individual probabilities for success are 1/4, 1/2 , and 5/8 , respectively, what is the probability that Xavier and Yvonne, but not Zelda, will solve the problem ? Answered by Stephen La Rocque. 





Probability tree 
20070519 

From Patrick: My question involves a video game called Guild Wars. In the game you can have modifications(mods) on items. One such mod is that you have a 20% chance to halve the casting time of a spell. You can have 2 of these mods available to you. Now, it is to my understaning that combined, you would have a 32% chance to halve the casting time and a 4% chance to quarter the casting time. Is this correct? Answered by Stephen La Rocque. 





Probability 
20070507 

From Danielle: A box contains 3 defective lights and 5 nondefective lights. The lights are tested one at a time without replacement. What is the probability that the 3 defective bulbs will be found in the first 3 tests?
is it 1/56 by chance? Answered by Stephen La Rocque. 





How to find the odds for a lottery jackpot 
20060412 

From Harvey: Is it best to use factorials to calculate the odds of winning a lottery, such as the MegaMillions that is popular in the US, or is there a better way? Answered by Stephen La Rocque. 





Random 
19980915 

From Hugh Ballantyne: I am an occasional teacher. Here is my question: Does the word "random" have a technical meaning in mathematics? Answered by Harley Weston. 

