Grades 1-2 Video Solutions 2022-2022_1-2

Video Transcription

Problem number 3. The picture shows 5 identical bricks. How many bricks are touching exactly 3 other bricks? 1, 2, 3, 4, or 5? There are 5 bricks in the picture.  So if a brick is touching each of the other bricks, it's touching 4 bricks, which is more than we are looking for. First, let's consider the vertical bricks on this side.  They touch each other, and each one touches each of the 3 horizontal bricks on the left side. So these 2 touch 4 bricks, not 3.  On the left side, the one in the middle is touching the 2 next to it, as well as the 2 vertical ones, because all the bricks are touching the vertical bricks.  So this one is touching 4 bricks, so it's not one that we're looking for. That leaves the top brick and the bottom brick. They are touching the vertical bricks here,  but they're separated from each other by this brick in the middle. So they are each only touching 3 bricks.  So these 2 are the only 2 bricks that are touching exactly 3 other bricks. The answer is B, 2.

Video Summary

The problem involves determining how many of 5 identical bricks are touching exactly 3 other bricks. By examining the arrangement, it's noted that the two vertical bricks touch 4 others, while the middle horizontal brick touches 4 as well. However, the top and bottom horizontal bricks each only touch 3 others, as they are separated by the middle brick. Thus, 2 bricks are touching exactly 3 other bricks. The answer is 2.

Keywords

bricks

arrangement

touching

vertical

horizontal