You are offered an investment opportunity. Its outcomes and probabilities are presented in the following table. X P(X) –$1000 .40 $0 .20 +$1000 .40 The mean of this distribution is _____________.
举一反三
- You are offered an investment opportunity. Its outcomes and probabilities are presented in the following table. X P(X) –$1000 .40 $0 .20 +$1000 .40 Which of the following statements is true?
- 【单选题】下列选项中能正确表达 0 成立的逻辑表达式的是 A. x>0 or x<5 B. x>0 and x<1000 C. x>0 & x<1000 D. x>0,x<1000
- 有一随机变量x~N(30, 25)，若P(x<20)＝0.0227，则P(x≥40)=
- 硬盘容量为40GB,相当于( )MB。 A: 40×1024 B: 40×1000 C: 40×1024×1024 D: 40×1000×1000
- 已知随机变量X服从B ( n , p )，E(X) = 4，D(X) = 3.6，则（ ）． A: n = 20，p = 0.2 B: n = 40，p = 0.9 C: n = 10，p = 0.4 D: n = 40，p = 0.1