Grades 1-2 Video Solutions 2025-2025_1-2

Video Transcription
Video Summary
Problem number nine. Two rubber bands are placed around a stack of 18 cubes. How many cubes are not touching a rubber band? In the picture, we can see that these three cubes on the bottom right side are not touching a rubber band, and by symmetry, these three cubes on the left side, even though we can't see all of them, cannot be touching a rubber band either, because we know that the red rubber band that goes vertically will touch the middle group of cubes, and the orange will touch the top layer. So this means that these three cubes on the right and these three cubes on the left will not touch a rubber band, and in fact, none of the other cubes are free of touching a rubber band. Like we've just mentioned, all the cubes in the top are touched by either the orange rubber band, which goes around the sides, or the red rubber band, which touches the top middle cube, and in the bottom layer, all of the cubes in the middle diagonal will be touched by this red rubber band, which goes across the bottom of the stack. This means that only the three cubes on the left and the three cubes on the right are not touching a rubber band. That means the answer is A, six.
Keywords
rubber bands
cubes
symmetry
touching
solution