Maximum variance given x values on an interval [a,b]

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Thanks in advance for the help.

I'm exploring a possible solution to a problem. In order to explore it, however, I need to find the maximum variance of a set of numbers on a given interval. For example, suppose I draw at random 5 continuous values from the interval [0,100]. Given these five values what is the maximum variance that I can expect?

What is the procedure to answering questions of this type?

note: I'm not sure what tags I should place on this under. I have picked statistics since the problem I wish to ultimately tackle is related to statistics. I have also added number theory for similar reasons. If there are any better tags please let me know.

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Variance measures how spread out they are, so with five numbers, put two of them at the one endpoint and three at the other. Thus: $0,0,0,100,100$. With an even number of numbers, put have of them at one endpoint and half at the other.

For $0,0,0,100,100$, the variance is $\left(\frac 3 5\cdot\frac 2 5\right)\cdot100^2$.

(Here I am using $\frac 1 n \sum_{k=1}^n (x_k-\bar x)^2$ where $\bar x=\frac 1 n \sum_{k=1}^n x_k$, and not $\frac 1 {n-1} \sum_{k=1}^n (x_k-\bar x)^2$, which should be used only in doing estimates based on a random sample. But either way, the answer above will be the same.)