Chapter 8 on probability distributions, reading notation

Question #22 is about probability distributions. We are given

X = [5,10]; Prob [Xi] = (Xi-3)/9

What do the 5 and 10 mean in the first part? Does this mean that X can equal 5 OR 10? Or does this mean that X can be any integer between 5 and 10 inclusive? Or does it mean that X can be any value between 5 and 10, which may include fractions?

The question says nothing about “uniform distribution”

Looks like it means that X can equal 5 OR 10 to me. The sum of all probabilities nicely equals 1 and the notation: Prob [Xi] = some number is typical of a mass function, if it was a continuous function (like the uniform distribution) you would have a density function f(x)=bla bla bla. And here the density doesn’t integrate to one over the interval

The notation used is pretty wrong and leads to confusion though, it should have been: X = {5 ; 10} instead.

As a mathematician, I’d be accustomed to seeing X={5, 10} (a comma, not a semicolon).

Apart from that, spot on: it’s a discrete distribution, not a continuous distribution.