<style>
.test_box {
display: -moz-box;
display: -webkit-box;
display: box;

...
}
.list {
width:200px;
}
.list_one {
-moz-box-flex: 1;
-webkit-box-flex: 1;
box-flex: 1;
}
.list_two{
-moz-box-flex: 2;
-webkit-box-flex: 2;
box-flex: 2;
}
</style>

<div class="test_box">
<div class="list list_two">1</div>
<div class="list list_one">2</div>
<div class="list list_one">3</div>
</div>