![]() ASL | A sieve is a way of getting rid of something you do not want. Then, you can keep what you want. This program will teach you how to use a special kind of sieve. This is a sieve in math, called the Sieve of Eratosthenes. |
![]() ASL | I like m & m's, but I only like the red ones. When I get a package of m & m's, I get rid of all of the other colors, except red. So, I throw out the brown, yellow, orange, and blue ones. This mean I only have the red ones left. This is kind of what the Sieve of Eratosthenes does. This sieve can help you find a special kind of number, called a prime number. |
![]() ASL | Prime numbers are numbers that can only be divided by 1 and itself. For instance, 2 is a prime number because 2 can only be divided by 1 and 2 evenly. Sometimes prime numbers can be hard to find. Rather than simply guessing at numbers and seeing if they are prime, Eratosthenes came up with a way to find prime numbers. He took a group of numbers and put them through his sieve. That way, he knew that he had found all of the prime numbers in that group of numbers. |
![]() ASL | When doing the model, try to find the pattern. Then, you will understand how the Sieve of Eratosthenes works! |
![]() ASL | In this activity, you will learn what prime and composite numbers are.
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