why does it add random numbers?

so im trying to make a progress bar but i ran into one issue

UIS.InputBegan:Connect(function()
    if vGame.Value then
        if bar.Size.X.Scale <= 1 then
            bar.Size = UDim2.new(bar.Size.X.Scale + 1/value,0,1,0)
            value = value - 1
            print(value)
        else
            vGame.Value = false
            bar.BackgroundColor3 = Color3.fromRGB(60, 182, 0)
            wait(5)
            script.Parent.Visible = false
        end
    end
end)

i think the problem comes from this line

bar.Size = UDim2.new(bar.Size.X.Scale + 1/value,0,1,0)

value is 200 which means 1/200 = 0.005

but roblox for some reason when i click, adds 0.004 or 0.006