Talk:Thunderbolt/@comment-95.245.99.202-20130610094252/@comment-6138928-20130610104040

P(E) = Explosion = 3/10 -> chance of first arrow to explode?

P(E|TA) = (9*3)/(10*10) = 27/100 -> chance of second arrow to fire and explode?

P(2E|TA) = P(E)*P(E|TA) = (30/100)*(27/100) = 8.1%