by bbirdwell Mon Jan 11, 2010 10:39 am
Hello R,
Let me try to explain. On this problem, we must try to identify a flaw in one of the speakers' arguments, so me must analyze each argument and try to predict possible mistakes, or gaps in the reasoning.
Sandy says "it's best" to play the lotto only after there have been a few weeks without a winner because the money pot increases.
Alex disagrees, saying that one is more likely to win when the pot is small because fewer players are playing.
We can see that Alex makes the biggest mistake in logic here. When playing a lottery game based on choosing numbers that are to be drawn, your chances remain the same no matter how many other people are playing.
For example, let's pretend that you and I are playing a game where each of us selects one number between 1 and 10, and then the numbers 1-10 are thrown into a hat and one is drawn out. Your chances of winning are 1 out of 10. If we ask everyone in Boston to play the game, your chances of winning are still 1 out of 10. The number of people playing does not affect the probability of your guessing the winning number.
Thus, answer choice (B) is correct.
Answer choice (E) is incorrect because Sandy does not actually do what (E) suggests that she does. We know from the argument that Sandy believes it is BEST to play the lottery when no one has one it in quite awhile. She does not say, as (E) suggests, that the chances of there being a winner increase.
Hope that helps!