已知随机变量X与Y相互独立,则下列结论正确的是( )
A: 若X~B(10,0.3), Y~B(15,0.2),则X+Y~B(25,0.5)
B: 若X~P(1.2), Y~P(0.8),则X+Y~P(2)
C: 若X~N(2,5), Y~N(1,4),则X-Y~N(1,1)
D: 若X~E(0.1), Y~E(0.1),则min{X,Y}~E(0.1)
A: 若X~B(10,0.3), Y~B(15,0.2),则X+Y~B(25,0.5)
B: 若X~P(1.2), Y~P(0.8),则X+Y~P(2)
C: 若X~N(2,5), Y~N(1,4),则X-Y~N(1,1)
D: 若X~E(0.1), Y~E(0.1),则min{X,Y}~E(0.1)
举一反三
- 若X~N(3,0.2),Y~N(2,0.3),且X与Y相互独立,则X+Y~( ) A: N(5, 0.1) B: N(5, 0.5) C: N(1, 0.1) D: N(1, 0.5)
- 设随机变量X和Y相互独立且X~N(0,1),Y~N(1,1),则( ). A: P{X + Y £ 0} = 1/2 B: P{X + Y £ 1} = 1/2 C: P{X - Y £ 0} = 1/2 D: P{X - Y £ 1} = 1/2
- 独立随机变量 X , Y ,若 X ~ N ( 1 , 4 ), Y ~ N ( 3 , 16 ),则 E ( X - Y )=( ) D(X-Y)=( )
- 若X~P(0.2),Y~P(0.3),且X与Y相互独立,则X+Y~
- 【单选题】设随机变量X和Y的分布律为P{X=0, Y=0}=0.1, P{X=0, Y=1}=0.2, P{X=1, Y=0}=0.3, P{X=1, Y=1}=0.1, P{X=2, Y=0}=0.2, P{X=2, Y=1}=0.1, 则Z=max{X,Y}的分布律中P{Z=1}=() A. 0.1 B. 0.3 C. 0.4 D. 0.6