We have three unknown quantities here, Shania: the number of towels, umbrellas, and chairs sold. Using the info listed in the problem, let's call the number of umbrellas sold x and the number of chairs sold y. We are told that the numbers of towels sold is 3(x + y). In fact, we are told that 54 towels are sold. We can now form the following equation:
54 = 3(x + y)
Remember though, the problem states that 12 umbrellas were sold. Since x = the number of umbrellas sold, we can substitute into our equation.
54 = 3(12 + y)
This is now an equation with a single variable. You should be able to solve this for y, Shania.
