Answer:
professor's efficiency is 75%
Step-by-step explanation:
given data
expected cover = 16 chapters
able to cover = 12 chapters
to find out
the professor's efficiency
solution
we know here that when professor works at 100% efficiency
then complete 16 chapter in 1 semester
but here Professor completed only 12 chapter
so for 100% we know 16 chapter that is
100% = 16 chapter
and for x% = 12 chapter
so from above both equation we get x %
x = 100 % ×
x = 75%
so we can say that professor's efficiency is 75%