The life of a light bulb manufactured by a company is found to be normally distributed. if the bulbs last 400 days with a standard deviation of 75 days, what is the probability that a randomly chosen light bulb lasts?(adsbygoogle = window.adsbygoogle || []).push({});

a) at least 450 days?

b) less than 150 days?

etc.

Throughout the examples in the book im studying, i am not making much sence of this.

Would be appreciated for some advice were to start.

Thanks

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# Homework Help: Normally Distributed.

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