DescriptionThis is the fourth clip in a series of seven of building towers four tall problem using red and blue unifix towers. The researcher tells them to write on a paper the towers they had created. She tells them to agree, teaching them representation. She advises them to organize them by lining them up in the manner they will draw them on paper. Brian asks Jeff to explain how he got all the towers implying that he either didn’t understand something about the solution. The researcher confirms how many they have, and they say seventeen towers. She asks them how they checked to know that they have all the possible towers. Brian counterchecks by moving one tower at a time beside the already created towers. They continue using a guess and check strategy to build a random tower and check it for duplication. He identifies a duplicate tower and puts it aside. They get amazed after finding that they have sixteen towers. Jeff changes his answer on paper to sixteen. The other students get 16 towers and they keep shouting it out.