Acertain test preparation course is designed to students improve their scores on the lsat exam. a mock exam is given at the beginning and end of the course to determine the effectiveness of the course. the following measurements are the net change in 6 students' scores on the exam after completing the course: 23,18,23,12,13,23using these data, construct a 80% confidence interval for the average net change in a student's score after completing the course. assume the population is approximately normal.

Interval [16.34 , 21.43]

Step-by-step explanation:

First step. Calculate the mean

Second step. Calculate the standard deviation

As the number of data is less than 30, we must use the t-table to find the interval of confidence.

We have 6 observations, our level of confidence DF is then 6-1=5 and we want our area A to be 80% (0.08).  

We must then choose t = 1.476 (see attachment)

Now, we use the formula that gives us the end points of the required interval

where n is the number of observations.

The extremes of the interval are then, rounded to the nearest hundreth, 16.34 and 21.43

step-by-step explanation:

bob the banana

when rotating a figure 180 degrees, imagine that you are able to take the figure and turn it clockwise or counterclockwise around a center point. to rotate a figure 180 degrees, you will need to apply the rule (x, y) → (-x, -y). start by using a coordinate grid with coordinates for each vertex of the figure. the center point of the coordinate grid is located at (0, 0), which is what you will rotate the figure around. write down the original coordinates of the shape you are going to rotate. then, apply the rule. for example, coordinate (1, 2) becomes (-1, -2). another example would be, coordinate (-4, -2) becoming (4, 2). after you change each original coordinate to the rotated coordinate, you will draw your new figure.

step-by-step explanation: