Answer:
The “E” indicates an arc welding electrode. The first two digits of a 4-digit number and the first three digits of a 5-digit number stand for tensile strength. So, “1” stands for an all position electrode, “2” for a flat and horizontal electrode, and “4” for a flat, horizontal, vertical down and overhead electrode
2 Dewey you can still go to get
The parameter used in the probability is the average number of students represented by u.
How to calculate the probability?
The confidence interval based on the information will be:
= 3.85 - 2.09(1.348 / ✓20)
= 3.22
Also, 3.85 + 2.09(1.348 / ✓20) = 4.48
The confidence interval simply means that one is 95% confident that the true mean is between 3.22 and 4.48.