The variability measures the closeness of the individual data provided. So, the most reliable sampling is the one with the lowest variability.
For this case, the question with the lowest sampling variability is question 3. Therefore, we can conclude that the answers to which of the questions are most reliable is question 3.
To do these problems, plug in a couple of values into the equations, and see the general shape of the graph. To ensure you were right, check them on an online graphing calculator. I highly recommend Desmos Graphing Calculator. Cheers!
Answer: 9
Step-by-step explanation:
(1.5 + x) / 2 = 2 .... multiply both sides by 2
1.5 + x = 2 * 2
1.5 + x = 4
x = 4 - 1.5
x = 2.5 meters per second