A random variable X takes values 1,2,...,n with equal probabilities. Determine the expectation, R for X and show that the variance, Q^2 is given by 12Q^2=n^2-1. Hence, find
P(|X-R|>Q) in the case n=100
The Attempt at a Solution
I can show that 12Q^2=n^2-1 but not the latter.
Substituting n=100, R=50.5 and Q=28.87
How can i continue from here?