Answer:
31.6%
Explanation:
it is given that
Area of Department X = 8,000 square feet
Area of Department Y = 5,000 square feet
Area of Department Z = 6,000 square feet
now the total area =

=
square feet
Percentage of area covered by Department Z =
%
=
%
=
%
percentage of overhead expenses applied to Department Z = percentage of area covered by Department Z
hence we have,
percentage of overhead expenses applied to Department Z = 31.6%