Q:

A way to sit 2 Divs next to each other when 1st Div width is unknown?

this is my first post on this forum. I've used this forum a tone before to find out help and it's always been really helpful and useful. Straight forward help.
My problem I have is I want 2 divs to sit directly next to each other. I'm making a blog page for a community dance group. I have the div siting next to each other by utilising the float:left property in CSS. I found that solution on StackOverflow, thanks!!
But I don't know the width of Div 1, as I want it to sit in the middle of the page.
My CSS code: 
.contentsWrapper{
margin-left:100px;
margin-right:100px;
margin-bottom:10px;
overflow:auto;
}
.blogWrapper{
float:left;
}
.archievesWrapper{
width:250px;
float:right;
}

Any help would be great!!

A:

May be that's you want. Write like this:
HTML
<div class="right">right</div>
<div class="left">left</div>

CSS
.left{
    background:red;
    overflow:hidden;
    height:30px;
}
.right{
    float:right;
    background:green;
    height:30px;
    width:250px;
}

Check this http://jsfiddle.net/6EufF/1/

