新gre數(shù)學(xué)的難度相當(dāng)于高中數(shù)學(xué)水平，只要大家認(rèn)真復(fù)習(xí)，在新gre數(shù)學(xué)考試中拿高分甚至拿滿分都是很有可能的。不過大家也不能忽略新gre數(shù)學(xué)中可能會出現(xiàn)的考點(diǎn)難點(diǎn)。下面，就為大家整理新GRE數(shù)學(xué)復(fù)習(xí)要點(diǎn):Conditional，希望對大家有所幫助。
Conditional
Probability of event A conditioned on the fact that event B has happened is called the conditional probability and written as P(AIB).
P(AIB)=Probability Both A and B happens/ Probability B happens.
Example:
A six-sided die with faces from 1 to 6 is rolled twice. What is the probability that the face 5 turned up on first try given that the sum of the two faces is 9?
P(sum of faces is 9)=4/36=1/9.
P(face 5 turns up on the first try and sum is 9)=(1/6)*(1/6)=1/36.
P(face 5 turned up on first try given sum is 9)=(1/36)*(1/9)=1/4
Remember:
If P(AIB)=P(A),then two events A and B are independent, that is occurrence of one does not influence the other
應(yīng)對gre數(shù)學(xué)考試的時候，考生不要過于緊張，把基本概念弄明白，再記住一些新版gre數(shù)學(xué)必備的詞匯，那么相信新版gre數(shù)學(xué)應(yīng)該沒有問題。