Answer:
78.88%
Step-by-step explanation:
We have been given that
The z-score formula is given by
For
For
Now, we find the corresponding probability from the standard z score table.
For the z score -1.25, we have the probability 0.1056
For the z score 1.25, we have the probability 0.8944
Therefore, the percent of the trees that are between 20 and 30 years old is given by
0.8944 - 0.1056
= 0.7888
=78.88%
Answer:
a)
The correlation coefficient for this case is very near to 1 so then we can ensure that we have linear correlation between the two variables
b)
Now we can find the means for x and y like this:
So the line would be given by:
Step-by-step explanation:
Part a
The correlation coeffcient is given by this formula:
For our case we have this:
n=4
The correlation coefficient for this case is very near to 1 so then we can ensure that we have linear correlation between the two variables
Part b
Where:
With these we can find the sums:
And the slope would be:
Now we can find the means for x and y like this:
And we can find the intercept using this:
So the line would be given by: