求助与分享-->pumpkin转移

rabbit

the probability that the string of lightbulbs will fail during thime period T=1-the probability that the string of lightbulbs will not fail during thime period T

the probability that the string of lightbulbs will not fail during thime period T=(1-0.06)^10

so the answei is : 1-(1-0.06)^10=Ｅ．　１－０．９４的十次方

rabbit

所有的可能性为1=fail 的可能+ not fail 的可能

not fail的必要条件是每一个bulb都not fail, 1个bulb NOT FAIL 的可能是（1-0.06），那么10个都NOT FAIL（即the string of lightbulbs will NOT fail)  的可能为（1-0.06）^10。

不知我讲清楚没？

rabbit

You are welcome.