Two things: Thing One. I too just received a copy of the REA AP Stat review book, and I went through one of the practice tests yesterday. I agree with Al (Coons), it is a valuable resource for review materials but found some glaring typos and I'm not sure, but some questions seem not to fit the syllabus topics (at least the syllabus I have)---poisson and hypergeometric distributions(??). However, there are many many questions and problems, and if they create questions and discussion from my students, I'm all for them.
Thing Two: Check this out, does this make sense: In the Sioux Falls (that's in South Dakota) paper last summer I found these numbers:
(Powerball is a multistate lottery, choose 5 of 45, and choose 1 of another 45, i.e. the "Powerball"!!!)
Sales of Powerball Lottery tix: $3.6 billion Number of Jackpots won: 65
Assuming $1 per play: 65 out of 3.6 billion plays were winners. That is about 1 winner for every 3.6billion/65=55,384,615 or approximately 1 in 55 million. The theoretical probability is 1 in 54,979,155 (ie. about 1 in 55 million) ( Law of Large Numbers???)
I know I haven't counted multiple winners of the same jackpot but.....
Gregg Drube T.F. Riggs High School 1010 East Broadway Pierre, SD 57501 (605) 773-7350 (605) 773-7360 (Fax) firstname.lastname@example.org