title: remove extra characters or a value from column
body: <p>How to remove the '/' and after the '/' value i.e, 25?</p>
  <p>sample:</p>
  <pre><code>   score
      10
      24
      19
      20/25
      18/25
      16/25
  </code></pre>
  <p>output:</p>
  <pre><code>score
  10
  24
  19
  20
  18
  16
  </code></pre>