Suppose that we have an assembly line which produces iPads. We wish to measure the Defective Probability, which is the probability that any randomly-selected iPad on the assembly line is not working properly. To estimate this probability, we will take a random selection of devices from the assembly line and test whether each one is defective or not. As an engineer, your design task is to determine how many iPad should be tested to ensure that there is at least a 95% chance that your estimate of the Defective Probability is within at least 0.05 of the true probability.
(a) Solve this design problem using Chebyshev's Inequality.
The solution is:
I don't understand where the 1/4 is from.