Montessori Teacher

Maple Ridge (Silvana Sam

Montessori Teacher
Continuing
The...

Teachers, rural schools

Anywhere (Peace River North School District

Located in the heart of the Peace Country...

Head Teacher: 2nd/3rd Grades - Mil...

Anywhere (Mills College

About Mills College:
Located in Oakland...

Grade:
MiddleSubject:
Mathematics |

Posted Tue Apr 25 08:22:27 PDT 2000 by Adam M.Ritchey (adamritchey@hotmail.com).

Lesson Plan

IUP, Indiana, PA

Materials Required: None

Activity Time: about 45 minutes

Concepts Taught: Upon completion of lecture on Egyptian Multiplication, these ninth

This lesson plan will be about a new type of algorithm that will help those of you with problems

multiplying numbers. This algorithm is entitled Egyptian Multiplication. This method was used and

developed by the ancient Egyptians. These were people who migrated from the fertile Sahara region of

Africa. The Egyptians had customs similar to those of the Ethiopians. The Egyptian civilization was one

of the greatest ancient civilizations. They were well organized and one of the more advanced of the

ancient civilizations. They had calendars, standard weight and measure system and a centralized

government.

Egyptians used a different way to write the numbers than we do. Their writing is called hieroglyphics.

This type used different pictures to stand for different numbers. The list that follows is what these

hieroglyphics look like:

Egyptians had an interesting way of doing multiplication. They used addition to get the answer of a

multiplication problem. They only had to memorize one multiplication table. That table would be the 2

times table. This method is still used in many rural communities in Ethiopia, Russia, the Arab World, and

the Near East.

The term that we use with Egyptian Multiplication is called Doubling. Doubling does just what it

sounds like. You take one number and either multiply it by 2 or you add it to itself. This is done

repeatedly until you get the other number. Below is an example of what you need to do using the

problem 22 x 21:

You first take either number, the 21 or 22. Here we used the 22. Then set up a little chart like we

have done. Put the number being doubled on the right hand side. On the left hand side you put the

"double number". You keep putting the corresponding double with the number that was doubled. Once

you get to a double larger than the other number you are multiplying then you can stop. Now you have to

find the double numbers that add up to the other number, in our case is 21. The doubles that add up to

21 are 1, 4, and 16. Take the corresponding numbers and add them together; 22+88+352=462. That

number is the product of 22 and 21. Below are some more examples:

After completing these examples with the help of the class. I would then ask them for some number

that they would like to see multiplied together using this method. We would do these together with the

class telling me the doubles of the number. After about 10-15 minutes of this activity, I would then ask

them for five more pairs of numbers that they want multiplied. Once I write the numbers on the board, I

would tell them to copy these down and do them for homework that would be collected tomorrow in class

and is worth the same amount as a quiz. Before our departure, I ask them if they have any questions. If

so, I would answer them. I also remind them if they need extra help I would stay after school for about 2

hours.