Answer:
By the Empirical Rule, approximately 68% of the bulbs have lifetimes that lie within 1 standard deviation to either side of the mean.
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
Approximately 68% of the measures are within 1 standard deviation of the mean.
Approximately 95% of the measures are within 2 standard deviations of the mean.
Approximately 99.7% of the measures are within 3 standard deviations of the mean.
What percentage of the bulbs have lifetimes that lie within 1 standard deviation to either side of the mean?
By the Empirical Rule, approximately 68% of the bulbs have lifetimes that lie within 1 standard deviation to either side of the mean.
8x = 13
13 divided by 8
that would be 1.625
Answer: 0.965
Step-by-step explanation:
Given : Water use in the summer is normally distributed with


Let X be the random variable that represents the quantity of water required on a particular day.
Z-score : 

Now, the probability that a day requires more water than is stored in city reservoirs is given by:-

We can see that on comparing the above value to the given P(X > 350)= 1 - P(Z < b) , we get the value of b is 0.965.
180 degrees is half of a circle, and clockwise means turning in the direction a clock does - right.
So a point would be turned right halfway around.