The first step to solving this problem is figuring out what it is asking.The problem seems to be asking for how many robberies can occur with at least (meaning greater than or equal to) 24 suspects. To find how many robbers there are one should add the number of robbers from the north to robbers from the south. With the number of robberies in the north being x and the number of robberies in the south being y, and the number of suspects from each robbery on the north being 4 and the number of suspects in each robbery from the south being 2, one can multiply 2 by y to find the suspects on the south side, and 4 by x to find the number of suspects in the north. Doing this, and then adding the two quantities gives us 2y + 4x. Then, since we know that there are at least 24 suspects, we know that 2y + 4x is greater then or equal to 24. This gives us the answer of 2y + 4x => 24.