Activity – Composite Numbers

Do the following activity below. The aim is to sort out numbers from 1 to 100 according to the different ways they can be expressed as a product of smaller numbers. 

Step 1: Rule out two columns on the sheet of paper you provided. Label one column as “Only 2 Factors”, and the other column as “More than 2 Factors”.

Step 2: Click inside the box, type 1, and press Enter on your keyboard. You should have the product 1 x 1.

Step 4: Click in the box again, type 2, and press the Enter key. You should have 2 x 1.

Step 5: Continue this process until you reach 100.

-If you find a number that has only one other number apart from 1, write it under “Only 1 Factor”.

– If you find a number that has two or more other numbers apart from 1, write it under “More than 2 factors”.

1. With the exception of 1, (since 1 did not have another number) how many numbers went under the column for “Only 2 Factors” ?

2. How many numbers went under the column for “More than 2 Factors” ?

3. What name is given to numbers that have only factors ?

4. Can we refer to numbers with more than two factors as rectangular numbers ? (Hint: The circle patterns).

5. What is another name for numbers that can be written as a product of at least two other numbers ?