hope this document helps! it's kinda hard to type out the explanation but ill try
divide the percenatge by the molar mass of the element.
(do this for both elements) \
find the lowest number and divide the results with it
now you have your empirical formula (with the rounded answers)
then find the molar mass of your empirical formula
divide the number given (267) by the molar mass to get a rounded number.
multiply that rounded answer to your empirical formula to get your empirical formula. :)