GMAT
题目
2 cards are drawn at random (with replacement) from six cards numbered from 1 to 6 such that the sum of the numbers on the cards is 6.
Quantity A
Probability that one of the two cards drawn is numbered 3
Quantity B
解析
样本空间 = {(1,5),(2,4),(3,3),(4,2),(5,1)}
符合条件的结果为(3,3)
因此概率P = 1/5
答案为B
在线客服
官方微信
公众号