Answer:
a)Slope:
Intercept:
b)
And the determination coeffecient is
Step-by-step explanation:
Data given and definitions
The correlation coefficient is a "statistical measure that calculates the strength of the relationship between the relative movements of two variables". It's denoted by r and its always between -1 and 1.
The sum of squares "is the sum of the square of variation, where variation is defined as the spread between each individual value and the grand mean"
When we conduct a multiple regression we want to know about the relationship between several independent or predictor variables and a dependent or criterion variable.
n=110,

Part a
The slope is given by this formula:
If we replace we got:
We can find the intercept with the following formula
We can find the average for x and y like this:
And replacing we got:
Part b
In order to calculate the correlation coefficient we can use this formula:
For our case we have this:
n=110,
So we can find the correlation coefficient replacing like this:
And the determination coeffecient is
Answer:


And using a calculator, excel ir the normal standard table we have that:

And we can calculate the probability like this:
Step-by-step explanation:
A random sample of 36 observations has been drawn from a normal distribution with mean 50 and standard deviation 12. Find the probability that the sample mean is in the interval 47<=X<53. Is the assumption of normality important. Why?
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
and 
Since the distribution for X is normal then we know that the distribution for the sample mean
is given by:

We can find the probability required like this:


And using a calculator, excel ir the normal standard table we have that:

And we can calculate the probability like this:

For this case we have that by definition:
- <em>The terms of a polynomial expression are those that are composed of coefficients and variables separated by signs of addition and subtraction.
</em>
We then have the following expression:

According to the definition, we can conclude that the first term is given by:

Answer:
The first term of the expression is:

Answer:gui
Step-by-step explanation:
The Tip will be $5.30
So the total she’ll pay is $31.80