title: MaterialUI set grid item width and spacing (e.g. have 10 items on row)
body: <p>How do I change the width of a grid item when it is not a whole [1..12] number? For example, if I want to have 10 items in a row that is <code>12/10=1.2</code>, but when I set <code>xs={1.2}</code> I get an error:</p>
  <pre><code>Warning: Failed prop type: Invalid prop `xs` of value `1.2` supplied to `ForwardRef(Grid)`, 
  expected one of [false,&quot;auto&quot;,true,1,2,3,4,5,6,7,8,9,10,11,12].
  </code></pre>