Material UI v1 – set table column widths

Try using colgroup, worked for me in Material-UI V1

<Table>
   <colgroup>
      <col style={{width:'10%'}}/>
      <col style={{width:'20%'}}/>
      <col style={{width:'70%'}}/>
   </colgroup>
   <TableHead>
      <TableRow>
         <TableCell>Head1</TableCell>
         <TableCell>Head2</TableCell>
         <TableCell>Head3</TableCell>
      </TableRow>
   </TableHead>
   <TableBody>
      <TableRow>
         <TableCell>Data1</TableCell>
         <TableCell>Data2</TableCell>
         <TableCell>Data3</TableCell>
      </TableRow>
   </TableBody>
</Table>