[機統] 請問這題要如何解

[yihan88 (thinking)]

Ｍax runs a sales team of 50 people for Brim Bram International and
 looks at the record of his existing employees.
He finds that 20 % of them achieved sales of less than $10,000 last month,
24% of the sales force have been with BrimBram for less than 6 months and
30% of the sales force have not yet returned their expenses claims for
last  months .
He dicides to interview all of the people who are in all three groups.
It turns out that there are 4 people to be interviewed.

what does this tell about the correlation ( or alternatively independence )
between these characteristics?


我的理解是Ｐ（Ａ）＝0.2

我的理解是這樣

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→ yhliu       : P(A) = 0.2, P(B) = 0.24, P(C) = 0.30,
→ yhliu       : P(A∩B∩C) = 4/50 = 0.08 ≠ P(A)P(B)P(C)
→ yihan88     : 有辦法P(A) P(B)P(C)算出0.08嗎？