Question 24. There are two types of blocks, white and red. A small cube can be made using four white blocks or using one white and one red block. The large cube shown in the picture is made of small cubes. What is the smallest number of white blocks needed to make the large cube? If we take a closer look at our large cube, we notice that it is made up of eight small cubes, because it is made out of two by two by two. So we can start off by counting all the white blocks we can see. These first two are made up of four white blocks each. Next, we'll count the white faces that we can see, which are these ones, and these, assuming that these are the smallest number of white blocks necessary, will be made out of one white and one red block. Next, we have these two small cubes that have red faces only visible to us. We can assume that they will also have one white block each. As such, finally, there is one small block that is hidden from this perspective. To have the smallest number of white blocks, we will assume that the small cube is made using one white and one red block. Now all we need to do is sum up all these white blocks, and we will get our answer, which will be D, 14.

smallest number

white blocks

large cube

2x2x2

mixed block construction