Sieve of Eratosthenes

This virtual manipulative displays a grid containing numbers from 2 to 200. You can use it to explore patterns and relationships involving multiples.

Using this virtual manipulative you may:

• Remove multiples of a number
• Show multiples of numbers
• Reset the workspace
• Choose how many rows to display

Remove multiples of a number

Select the Remove Multiples option.

Click on any number showing. Repeat if you wish, to remove multiples of any remaining number. The chosen number will turn blue and all other multiples of the number will be removed (blanked out). Click and drag the scrollbar on the right edge of the workspace to display more rows.

Show multiples of numbers

Select the Show Multiples option. Click on any number. Repeat if you wish, to show the multiples of a second number. Multiples of the first number will be shown in blue. Multiples of the second number are highlighted in green. Click and drag the scrollbar on the right edge of the workspace to display more rows.

Reset the workspace

Click the Reset button, or select the Remove Muliples option or the Show Multiples option.

Choose how many rows to display

Type the number of rows that you want to display in the text field next to the Set button. Then click the Set button. There are 10 numbers on each row.