Answer:
Where 
the mean and 
the deviation
Since the distribution for X is normal then we can conclude that the distribution for the sample mean 
is given by:
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".
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 the mean and the deviation
Since the distribution for X is normal then we can conclude that the distribution for the sample mean is given by:
Answer: The range of the medians of the numbers left and right of the median of the entire data set.
Answer:
The answer would be 8.
Step-by-step explanation:
This is a percentage question, and I have struggled with these before but this is the <em>easiest</em> way to solve it given these certain criteria.
Alright, so it's given that:
A) 90%= an A grade
and
B) This is an 80-question test.
Given these, we can do the following:
90% times 80, which equals <em>72</em>.
Just to check, we know that to convert percentages to fractions, we move the decimal two spots to the left, therefore 90%= 0.90, or 0.9. We take 72 and divide it by 80, and we get 0.9, thus showing that it is correct.
Then, we do 80-72 and using simple math we get 8.
You need to solve the following equation:
-0.5x^2 +36x -161 = 451
Set right side to 0
-0.5x^2 +36x -612 = 0
Multiply by -2 to get rid of decimal and leading neg coefficient.
x^2 -72x + 1224 = 0
Use quadratic formula:
a = 1, b = -72, c = 1224
Therefore the min price to have 451 profit is $27.51
I would say B to your answer. # ask my brother in high school
~JZ
