This is because of points C, A, and B are all collinear, which means that they all fall on the same line. Since the points are collinear, the sum of CA and AB is the whole line, which is CB. I really hope this helps :)
<span>The sum of angles CAD and DAB is 180 degrees. This is because they are all on a straight line (because points CAB are colinear) and angles on a straight line add up to 180 degrees.</span>
The mean of the problem is 37.3. All you need to do is add all the numbers together and then divide them by the amount of numbers. So I added them all and divided by 10.
