How do I round numbers?

I'm making a script that uses an equation to calculate the distance between 2 objects, then moves 1 object to the other in a certain Time, and the speed at which it goes to the other part is dependent on the Time. Problem is, these equations will often give numbers with a crazy amount of numbers after the decimal, this causes all sorts of weirdness, such as the part missing its target. How would I round up the numbers so I don't get such crazy numbers?

--Cup goes to position 1
local Time=4
			local Distance=(math.abs(Cup.Position.X+Pos1.Position.X))
			local StudsPer=(Time/Distance)
			local TimeUp=0
			------------
			repeat
				wait(StudsPer)
				Cup.CFrame=Cup.CFrame*CFrame.new(0,0,StudsPer)
				TimeUp=TimeUp+StudsPer
				
			until
				TimeUp>=Time
				do Cup.Position=Pos1.Position--Ensures it gets there in case of bugs

There are two methods to rounding the two are, math.ceil() and math.floor(). as you can imagine ceil is short for ceiling so it rounds up, and floor is well... floor, so it rounds down. These are very simple to understand.

Example:

local rounddown = 12.5
local roundup = 12.5

print(math.ceil(roundup)) --prints 13
print(math.floor(rounddown)) --prints 12