You will be given a definition of a task first, then an example. Follow the example to solve a new instance of the task.
The task is to generate the correct answer for a given math problem.

a multiple choice test consists of 4 questions, and each question has 5 answer choices. in how many r ways can the test be completed if every question is unanswered ?
Solution: 625
Why? Total r of 5 * 5 * 5 * 5 = 5 ^ 4 = 625 ways to answer all of them. Therefore, the answer is 625.

New input: Problem: in a certain apartment building , there are one - bedroom and two - bedroom apartments . the rental prices of the apartment depend on a number of factors , but on average , two - bedroom apartments have higher rental prices than do one - bedroom apartments . let r be the average rental price for all apartments in the building . if r is $ 5,600 higher than the average rental price for all one - bedroom apartments , and if the average rental price for all two - bedroom apartments is $ 10,400 higher that r , then what percentage of apartments in the building are two - bedroom apartments ?
Solution:
35 %