Preloader Actionscript problem

Question

As a relative newcomer to Actionscript, I came across a
preloader tutorial (from a trusted source) which reveals a cut out
photograph as the movie loads. I decided to use it, but although I
have checked and double-checked the Actionscript, Flash 2004 keeps
reporting an error and the preloader is not working.
The problem is obviously in line 6 and I just thought that
someone might be able to look at the Actionscript and see the
problem (which I can't!).
Here's the Actionscript;
stop();
mask_mc._height = 1;
this.onEnterFrame = function() :Void {
var loadedData:Number = this.getBytesLoaded();
var allData:Number = this.getBytesTotal();
var percent:Number = Math.round(loadedData/allData=100);
mask_mc._yscale = percent;
if (loadedData>=allData) {
gotoAndStop(10);
delete this.onEnterFrame;
Here's the error report from Flash;
**Error** Scene=Scene 1, layer=Actions, frame=1:
Line 6: Left side of assignment operator must be variable or
property.
var percent:Number = Math.round(loadedData/allData=100);
Total ActionScript Errors: 1 Reported Errors: 1
Many thanks for any help.

Answer 1

you have an assignment operator (=) where you should have a
multiplication operator (*) at the END of that line.