[Closed] MXS: Get random value through certain step?

How to get a random value from a set of numbers only after a certain step?
Suppose I need to randomly move several objects in the range from 0mm to 500mm, but I need to make sure that they move randomly through 100mm. How to make it a script?
If the random command had the Step parameter, that would be good. But there is no such thing, so I cannot understand how I can make such a random shift through a certain step.
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