title: Rounding in steps of 20 (or X) in JavaScript?
body: <p>I have numbers starting at 50 and ending with 190. The steps are alwyas 20 --> </p>
  
  <p><em>50, 70, 90, .... 190</em></p>
  
  <p>Now I get a number from a text filed which has to be rounded according to this. So if I get 55, it should become 70, if I get 77, it should be 90. If I get 90, it should of course stay 90. I know how to do it steps of 10:</p>
  
  <pre><code>// 55 --&gt; 60
  number = Math.ceil(number / 10) * 10
  </code></pre>
  
  <p>How to round the number I get using steps of 20?</p>
  
  <p>Thanks!</p>