title: Scaling between two number ranges
body: <p>I remember using an equation to do this at some point – how do you do this in Javascript?</p>
  
  <p>Plugin two number ranges:</p>
  
  <pre><code>rangeX = 1 (through) 10;
  rangeY = 300.77 (through) 559.22;
  </code></pre>
  
  <p>Input a value in the rangeY scale:</p>
  
  <pre><code>inputY = 328.17;
  </code></pre>
  
  <p>Convert to proportional value in rangeX scale:</p>
  
  <pre><code>outputX = 1.43;
  </code></pre>