Add or Subtract
<p>basically what im trying to do is have a number of stock (lets say its, 100) and an inventory list displaying the stock sold or added . how do i code it to say if it is a minus number , on the inventory list, (e.g -55) to take it away or if it is a positive number (i.e 45 to add it on instead of taking it away) ??</p>

<p>Cheers</p>
