Question

用甲、乙两炮向某目标各发两发炮弹,命中率分别为0.7和0.8,设目标在命中一发、二发、三发或四发炮弹后被击毁的概率分别为

Answer 1

一发命中概率p1=(2*0.7*0.3*0.2*0.2+2*0.8*0.2*0.3*0.3)*0.5=

二发命中概率p2=(0.7*0.7*0.2*0.2+0.8*0.8*0.3*0.3+2*0.7*0.3*2*0.8*0.2)*0.6=

三发命中概率p3=(0.7*0.3*0.8*0.8*2+0.7*0.7*0.8*0.2*2)*0.7=

四发命中概率p4=(0.7*0.7*0.8*0.8)*0.8=

我现在没计算器,本人计算能力极差,所以有借口偷懒,望楼主见谅!