This task is from Tools 4 NC Teachers. Students consider different strategies to multiply a 3-digit number by a 2-digit number. This is remixable. 

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Manuel and Emani both solved the problem 341 x 25 using an algorithm.   (picture available when you download the file) 

How would you explain to a friend how Manuel’s strategy works?  Where does the 5 come from? Where does the 100 come from?  Where does the 1,500 come from?  What about the 20, 400, and 6,000?

How would you explain to a friend how Emani’s strategy works?  What does the 1 over 321 mean?  Where did 1,605 come from?  Where did 6,420 come from?

Emani used the U.S. Standard Algorithm.  Manuel used a different algorithm.  What is the same about both algorithms?  How are the two algorithms different?