Is your class 14 L of 11% alcohol solution must be mixed with the 20% solution to get a 13% solution how many liters of the 3% solution are needed

There are 1872 steps in a building that has 104 floors. each floor has the same number of steps. a second building has the same number of floors but 2 fewer steps between each floor. how many steps are there between each floor of the second building?