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
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 theoption. 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 thebutton, or select the option or the option.
Choose how many rows to display
Type the number of rows that you want to display in the text field next to thebutton. Then click the button. There are 10 numbers on each row.