Merge pull request #3628 from frankzhao/master

Fix a few typos in the ExpressionWidget [ci skip]

frontend/src/metabase/query_builder/expressions/ExpressionWidget.jsx

@@ -53,8 +53,8 @@ export default class ExpressionWidget extends Component {
                             onError={(errorMessage) => this.setState({error: errorMessage})}
                         />
                         <p className="h5 text-grey-2">
-                            Think of this as being kind of like writing a forumla in a spreadsheet program: you can use numbers, fields in this table,
-                            mathematic symbols like +, and some functions.  So you could type, Subtotal - Cost.
+                            Think of this as being kind of like writing a formula in a spreadsheet program: you can use numbers, fields in this table,
+                            mathematical symbols like +, and some functions.  So you could type, Subtotal - Cost.
                             <a className="link" href="http://www.metabase.com/docs/latest/users-guide/03-asking-questions.html#creating-a-custom-field">Learn more</a>
                         </p>
                     </div>