Answer:
Where
and 
Since the distribution for X is normal then the distribution for the sample mean is also normal and given by:



So then is appropiate use the normal distribution to find the probabilities for 
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean". The letter
is used to denote the cumulative area for a b quantile on the normal standard distribution, or in other words: 
Solution to the problem
Let X the random variable that represent the variable of interest of a population, and for this case we know the distribution for X is given by:
Where
and 
Since the distribution for X is normal then the distribution for the sample mean
is also normal and given by:



So then is appropiate use the normal distribution to find the probabilities for 
Hi! So if we lay out 16 popcorn balls, and each time we take away four, this is what would happen gradually,
16 bottom + 12 1st layer + 8 2nd layer + 4 3rd layer
16+12+8+4 = 40 popcorn balls!
( don't forget to use lables)
Answer:
the answer is E. none of the above
She started with x boxes.
Then she bought 7 more, so now she has x + 2.
Then half of the boxes were destroyed.
She now has (x + 7)/2.
She has 22 boxes.
(x + 7)/2 = 22
x + 7 = 44
x = 37
She started with 37 boxes.
Answer:
feet
Step-by-step explanation:
We will use the Pythagorean Theorem to solve this. Which states that:
One Length^2 + Another Length^2 = Hypotenuse^2
We can take one length as 5 ft and another length as 9 ft and we call the hypotenuse "h", so we have:

Now, let us solve for "h":

The pond's hypotenuse is about 10.3 feet