Multiplication Tables For Adults

In about the third grade, I learned my multiplication tables.  Just the other day, I learned them again, only this time the multiplication tables were a little different.  This time they were in base-five.  It was fun watching the other students in my math class taking their time to carefully calculate the multiplication table in base-five.  They looked like many of the students in my third grade math class, learning multiplication for the very first time.  One thing is for sure, the rules and properties of multiplication stay the same whether in base-five or base-ten.  The difference is definately in grouping the numbers.  As you might remember from one of the earlier posts, base-five is groups of five, while base-ten is groups of ten.

An easy way to look at multiplication of whole numbers is by remembering them as repeated addition.  An example of repeated addition is 4x5, that is 5+5+5+5.  So, 4x5=5+5+5+5=20.  Shown in the picture below from http://elko.k12.nv.us/webapps/vmd/mathdictionary/htmldict/english/vmd/full/m/multiplication.htm.

  In class we also learned about multiplication models.  The three models that we went over are the rectangular array, tree diagram, and partial products.  I really like the tree diagram, even though it may be hard to work with when you are using large numbers.  It really is pretty fun.  Here's a website to see how tree diagrams work:  http://www.regentsprep.org/Regents/math/ALGEBRA/APR4/PracTre.htm

I also want to include some information about the rectangular array and partial products.  The picture below is from another blog that I found interesting:  understandingmultiplication.blogspot.com/2007/03/third.html.

A video that may be helpful to understand partial products is:


Until next time...