: invalid argument #2 to 'random' (interval is empty)?

Looks like your running in to your X value going negative math.random() doesn't like negative values. So I would Flip the X Value to positive then pass the new value to the math.random() function then times the value by-1 if it was negative

For example in code: (Old answer Code)[INT]

local InaccuracyPossibility = Vector3.new(-5,1,2)

for i=1, 10 do
	local bisXNeg = InaccuracyPossibility.X <= 0 -- See if the XValue is negative or not

	local XAbs = math.abs(InaccuracyPossibility.X) -- Grab the abs of x

	-- pass the Abs(X) then if its negative then times this value by -1

	local XRandom = math.random((0 - XAbs), XAbs ) * (bisXNeg == true and -1 or 1)
	print(XRandom)
end

Output:

 2 
 -3
 -1
 -0
2
-1
-0
4
-1
3

(New Answer Code)[NUMBER(FLOAT)]

local InaccuracyPossibility = Vector3.new(-5.02,1.2,2.5)

for i=1, 10 do
    local bisXNeg = InaccuracyPossibility.X <= 0 -- See if the XValue is negative or not

    local XAbs = math.abs(InaccuracyPossibility.X) -- Grab the abs of x

    -- pass the Abs(X) then if its negative then times this value by -1
	-- Removed the (0-XAbs) and replaced it with the following
	local XRandom = (math.random()*XAbs) * (bisXNeg == true and -1 or 1)
    print(XRandom)
end

Output:

  -2.5070609002733
  -0.61484114847888
  -1.7726778006567
  -1.0249097790085
  -0.40516958552847
  -2.1358409614483
  -3.7283219967974
  -4.8174073688361 
  -1.6732552332573
  -4.0884841332942

i havent tested it in Roblox but it's working in notepad++ with a lua plugin! (im on my phone lolz) :P

hope this helps!