Student enrollment at a local school is concerning the community because the number of student has dropped to 504 which is a 20% decease form the previous year. what was the student enrollment the previous year?

Since 504 is equal to 80% od the previous years enrollment you would divide 504 by 80 which gives you 6.3 which is 1% of the previous years enrollment.  You would then multiply 6.3 by 100 in order to find 100% of the previous years enrollment.  to check your work divide 630 by 20% or .20 which will give you 126. You then subtract 126 from 630 which gives you 504.

24 is the correct answer.