the life of a certain brand of battery is normally distributed, with mean 128 hours and standard deviation…

the life of a certain brand of battery is normally distributed, with mean 128 hours and standard deviation 16 hours. what is the probability that a battery you buy lasts at most 100 hours? standardize the variable. x = 100 is equivalent to z = -0.57 0.57 -1.75 1.75 done
Answer
Answer:
-1.75
Explanation:
Step1: Recall z - score formula
The formula for the z - score is $z=\frac{x-\mu}{\sigma}$, where $x$ is the value from the original normal distribution, $\mu$ is the mean, and $\sigma$ is the standard deviation.
Step2: Identify values
We are given that $\mu = 128$, $\sigma=16$, and $x = 100$.
Step3: Calculate z - score
Substitute the values into the formula: $z=\frac{100 - 128}{16}=\frac{-28}{16}=-1.75$.