Multiplying two text boxes

Strange problem, least I think it is I just can’t work out how to multiply two text boxes and then display it in another text box. I have tried the following but had no luck should these work thus some other code is messing it around or would non of these work;

box1.text = box2.text * box3.text;

box1.text = number(box2.text) * number(box3.text);