SAT數(shù)學(xué)“概率論”部分難題選講

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SAT數(shù)學(xué)對(duì)中國(guó)學(xué)生確實(shí)是比較簡(jiǎn)單的一項(xiàng),而且SAT拿滿分也是比較容易的。但是SAT數(shù)學(xué)部分卻總不能如愿的拿到滿分,究其原因,除了英文環(huán)境下題目理解錯(cuò)誤之外,還有一點(diǎn)就是國(guó)內(nèi)高中學(xué)到的解題技巧都沒(méi)有積極應(yīng)用,所以導(dǎo)致了解題繁瑣,不但浪費(fèi)了時(shí)間,而且還使得答案錯(cuò)誤。
     各位考生一定要注意,對(duì)SAT數(shù)學(xué)來(lái)說(shuō),你用的方法越簡(jiǎn)單,你做對(duì)的概率越大,而且還可以在考場(chǎng)上省出很多時(shí)間來(lái)做更有意義的事情。
    下面我們就對(duì)SAT數(shù)學(xué)概率論部分的常用解題技巧進(jìn)行總結(jié),以期事半功倍:
    (1)In the integer 3589 the digits are all different and increase from left to right. How many integers between 4000 and 5000 have digits that are all different and that increased from left to right?
    比較題目:(2)In the integer 3589 the digits are all different and increase from left to right. How many integers between 30000 and 50000 have digits that are all different and that increased from left to right?
    (3)If p, r, m are three different prime numbers greater than 2, and n=p*r* m, how many positive factors, including 1 and n, does n have?
    比較題目:(4)If p, r, m, n, t and s are six different prime numbers greater than 2, and n=p*r*s*m*n*t, how many positive factors, including 1 and n, does n have?
    (5)If someone throws a dice twice, on the first time he gets a points, and on the second he gets b points, what is the probability a/b>1?
    比較題目:(6)If someone throws a dice twice, what is the probability that the point he gets on one throw is bigger than the other?
     (7)Mr. Jones must choose 4 of the following 5 flavors of jellybean: apple, berry, coconut, kumquat, and lemon, How many different combinations of flavors can Mr. Jones choose?
    
    總之,做SAT數(shù)學(xué)在讀懂題目的基礎(chǔ)上,一定要使用簡(jiǎn)單的方法來(lái)做?。?BR>