title: Getting ufunc 'true_divide' although both variables have datatype object
body: <pre><code>a = sum(df1['P']*df1['Q'])
  b=sum(df1['Q'])
  c = a/b
  
  UFuncTypeError: ufunc 'true_divide' cannot use operands with types dtype('float64') and dtype('&lt;M8[ns]')
  </code></pre>
  <p>Here I am getting an error although the datatypes of both P and Q is object.</p>