​x
 
<!DOCTYPE html>
<html>
<body>
​
<h1>JavaScript 数字</h1>
​
<p>浮点的算数并不总是 100% 精准：</p>
​
<p id="demo"></p>
​
<script>
var x = 0.2 + 0.1;
document.getElementById("demo").innerHTML = "0.2 + 0.1 = " + x;
</script>
​
</body>
</html>
​