Şöyle bir şey yapabilirsin hocam;

<!DOCTYPE html>
<html lang="tr">
<head>
	<meta charset="UTF-8">
	<title>Document</title>

	<style>
		.container {width: 100%; height: 300px; font: 12px Arial; color: #fff;}
		.left {width: 25%;  height: 300px; background-color: #CF5C00; float: left;}
		.center {width: 50%;  height: 300px; background-color: #84D500; float: left;}
		.right {width: 25%; height: 300px; background-color: #78005B; float: right;}
	</style>
</head>
<body>
	<div class="container">
		<div class="left">Sol Yazı</div>
		<div class="center">Orta Yazı</div>
		<div class="right">Sağ Yazı</div>
	</div>
</body>
</html>