设X~N(9,3p>2p>),Y~N(5,0.5p>2p>),则有( )成立。
A.P(6<X≤15)>P(4.5<Y≤6)
B.P(6<X≤15)<P(4.5<Y≤6)
C.P(6<X≤15)=P(4.5<Y≤6)
D.P(6<X≤15)>2P(4.5<Y≤6)
[单选题]设X~N(3,(0.2)p>2p>),则P(2X>6.8)=( )。A.Ф(3.4)B.1-Ф(3.4)C.1-Ф(2)D.Ф(2)
[单选题]正态分布N(10,2p>2p>)的中位数是( )。A.2B.4C.5D.10
[单选题]设某质量特性X~N(μ,σp>2p>)若公差幅度T=8σ,Cp为( )。A.0.67B.1C.1.33D.1.67
[单选题]从均值为μ方差为σp>2p>的总体中抽得一个容量为n的样本X1,X2,…,Xn,其中μ已知,σp>2p>未知,下列各项属于统计量的有( )。A.X1+X2+X3B.min{X1,X2,X3,…,Xn}C.X1+X2-μD.(X1-2μ)/σE.X1+X2+σ
[单选题]设X~N(3,0.04),则P(2X>6.8)=( )。A.Ф(2)B.1-Ф(2)C.Ф(3.4)D.1-Ф(3.4)
[问答题]设X、Y相互独立且同服从分布B(n,p),设Z=X+Y,证明Z~B(2p,p).
[问答题]设X、Y相互独立且同服从分布B(n,p),设Z=X+Y,证明Z~B(2p,p).
[单选题]设X-N(5,4),则P(2A.φ(1.5)-φ(1)B.φ(1)-φ(1.5)C.φ(-1)-φ(-1.5)D.φ(-1.5)-φ(-1)
[单选题]Stars 1 n Their EyesThe ScientificAmerican Book of the Cosmos edited by Dav
[单选题]Stars 1 n Their EyesThe ScientificAmerican Book of the Cosmos edited by Dav