Please provide me with detailed solution, thank you.
An urn contains 3 red, 4 white and 5 blue discs. Three discs are selected at random
from the urn. Find the probability that all three discs are of different colours, if the selection is without replacement. (Answer: 3/11)
probability 10 P
2014-09-15 10:44 am
回答 (1)
2014-09-15 2:36 pm
✔ 最佳答案
Number of way of 3 discs are of different colours───────────────────────────────
Number of all ways=(3C1) (4C1) (5C1)
────────────
(3+4+5) C 3 =3 × 4 × 5
────── = 60/220 = 3/11
12C3
收錄日期: 2021-04-24 23:22:26
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20140915000051KK00014