the life of a manufacturers compact fluorescent light bulbs is normal, with mean 12,000 hours and standard…

the life of a manufacturers compact fluorescent light bulbs is normal, with mean 12,000 hours and standard deviation 2,000 hours. seth wants to find the probability that a light bulb he purchased from this manufacturer will last no more than 14,500 hours. how many standard deviations above the mean is 14,500 hours? 1.25 1.5 2.5

the life of a manufacturers compact fluorescent light bulbs is normal, with mean 12,000 hours and standard deviation 2,000 hours. seth wants to find the probability that a light bulb he purchased from this manufacturer will last no more than 14,500 hours. how many standard deviations above the mean is 14,500 hours? 1.25 1.5 2.5

Answer

Answer:

A. 1.25

Explanation:

Step1: Recall z - score formula

The formula for the z - score is $z=\frac{x-\mu}{\sigma}$, where $x$ is the value, $\mu$ is the mean, and $\sigma$ is the standard deviation. Here, $x = 14500$, $\mu=12000$, and $\sigma = 2000$.

Step2: Substitute values into formula

$z=\frac{14500 - 12000}{2000}=\frac{2500}{2000}=1.25$. So 14500 hours is 1.25 standard deviations above the mean.