RNG help

[pulsar jungle]

Hi I need help with a better rng system

So the current script is just

local Num = math.random(1,100)
if Num <=70 then
print("Common")
elseif Num <=90 then
print("Uncommon")
else
print("legendary")
end

I want it to be more flexible and easier to configure so I can add 3% or even 0.1% and more

This is how it is working, it works pretty well but hard to calculate the chances when I want something new

[marble slate]

I would simply have a table as such:

local rarities = {
  {name = "Common", chance = 70},
  {name = "Uncommon", ...}
  ...
}
``` or how ever many rarities you have then loop through your rarities, if Num is larger than the rarity.chance then thats the one to spawn

while checking down the list however, make sure to have a cumulative of the previous chances so that the chance(numbers larger than "Num") gets smaller, aka more rare, by using a cumulative variable or smt