Lua Help with adding percent chance function to the script.

[Permamently]

Hello, so I'm thinking about adding a percent chance to this script:

function onUse (cid, item, fromPosition, itemEx, toPosition)


if(itemEx.itemid == 7385) then
doRemoveItem(item.uid)
doTransformItem(itemEx.uid, 8209)
doSendMagicEffect(toPosition, 28)
return true
end
end

Could someone help me adding this?
This should work like this:
-30 % chance,
-if success the item is transformed from id 7385 to 8209(like in the script),
-if fail the item about number 2382 which is specified here:

<action itemid="2382" event="script" value="upgrade.lua"/>

should be removed.
Thanks in advance.

 

[Moj mistrz]

function onUse(cid, item, fromPosition, itemEx, toPosition)
    if(itemEx.itemid == 7385) and math.random(10) <= 3 then  
        doTransformItem(itemEx.uid, 8209)
        doSendMagicEffect(toPosition, 28)
    else
        doRemoveItem(item.uid)
    end
    return true
end

Try this

 

[Permamently]

@Moj mistrz It's working, thank you.