While going through the css specificity concept, I understood the fact that it is calculated as a 4 parts

1) inline (1000)
2) id     (100)
3) class   (10)
4) html elments (1)

CSS with the highest rule will be applied to the corresponding element.

I tried the following example

Created more than 10 classes

<div class="a1"> ....
     <div class="a13" id="id1"> TEXT COLOR
     </div> ... 
</div>

and the css as

.a1 .a2 .a3 .a4 .a5 .a6 .a7 .a8 .a9 .a10 .a11 .a12 .a13 {
    color : red;
}
#id1 {
    color: blue;
}

Now, even though in this case there are 13 classes the weight is 130. Which is greater than the id.

Result -> JSFiddle CSS specificity