随机变量X~N(4.1),求P|X-4|>2,若P(X>K)=0.9332,求k=?,已知O(2)=0.9773,O(1)=0.8413,O(1.5)=0.9332
问题描述:
随机变量X~N(4.1),求P|X-4|>2,若P(X>K)=0.9332,求k=?,已知O(2)=0.9773,O(1)=0.8413,O(1.5)=0.9332
答
N(4,1)
P(|X-4|>2)
=P(X-4>2)+P(X-4k)
=P(X-4/1>k-4/1)
=O(k-4)=0.9332=O(1.5)
k=5.5