Given:
A surf instructor has an initial fee of $12 and charges $8 per hour for lessons.
To find:
The y-intercept and its location on the graph.
Solution:
Initial fee = $12
Variable fee = $8 per hour.
Let the total fee be y for x hours. Then,
Put x=0, to find the y-intercept.
Therefore, the y-intercept is 12.
Table of values for ,
x y
0 12
-1 4
Plot (0,12) and (-1,4) on a coordinate plane and connect them by a straight line.
Clearly, the y-intercept is located at (0,12).
Using the t-distribution, it is found that the 95% confidence interval for the mean number of people the houses were shown is (20.1, 27.9).
We have the <u>standard deviation for the sample</u>, hence the t-distribution is used to build the confidence interval. Important information are given by:
The confidence interval is:
In which t is the critical value for a <u>95% confidence interval with 23 - 1 = 22 df</u>, thus, looking at a calculator or at the t-table, it is found that t = 2.0739.
Then:
The 95% confidence interval for the mean number of people the houses were shown is (20.1, 27.9).
A similar problem is given at brainly.com/question/15180581