Need with this quick getting confused

School has 204 sixth grade students. if the sixth grade is 30% of the total school, how many students are in the middle school?

Consider the set of all four-digit positive integers less than 2000 whose digits have a sum of 24. what is the median of this set of integers?

The sum of these consecutive integers is equal to 9 less than 4 times the least of the integer. find the three integers