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Elementary Archive

Browse Elementary Prime Numbers
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Selected answers to common questions:
    Prime factoring.

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Prime Numbers [01/31/1997]

What are the prime numbers and why are they prime numbers?

Prime Numbers vs. Prime Factors [01/13/1997]

What is the difference between a prime number and a prime factor?

1 and 0 [11/4/1994]

Is 1 or 0 a prime number?

1 and 0: Prime or Composite? [10/06/1997]

Is the number one a prime or a composite number? Why? What about zero?

Abundant and Deficient Numbers [10/14/1997]

What are abundant and deficient numbers, and what are they used for?

Classifying the Number One [11/27/1998]

My students have learned about prime and composite numbers. What classification fits the number 1?

Composite Numbers [1/30/1996]

What are Composite Numbers?

Determining if a Large Number is Prime [05/05/2004]

Is 333667 a prime? I have ruled out all evens plus 5, 10, 7, 8, 9, 13, 17, and 19 as possible factors but do not know how to proceed from there.

Etymology of the Word Prime [08/28/2002]

Why are prime numbers called prime?

Factors and Multiples [01/27/1998]

My son is in 4th grade and needs help naming a common multiple of a pair of numbers.

Factors and Primes [09/10/1997]

A prime number is a number greater than 1 and has only 2 divisors, 1 and itself. Without the stipulation greater than one, what would be the effect?

How does the Sieve of Eratosthenes Work? [10/29/2002]

How does the Sieve of Eratosthenes work for finding prime numbers?

How many prime numbers are squares? [01/09/1997]

Can a prime number be a square?

Numbers with Large Exponents [08/22/2001]

How many zeros end the number 2^300 * 5^600 * 4^400?

Perfect Numbers [08/14/1997]

What is the highest perfect number that has been found? How many perfect numbers are there? What are they?

Perfect Numbers - Basics, History [11/3/1996]

What is the next perfect number after 28?

Prime and Composite Numbers, Sieve of Eratosthenes [01/28/1997]

I need a list of all prime numbers and all composite numbers up to 50.

Prime, Composite, or Neither? [09/16/2003]

What are prime and composite numbers?

Prime Numbers [9/20/1995]

What are prime numbers?

Prime Numbers: 20-30 [01/31/1997]

What are the prime numbers 20 through 30?

Primes and Repeating Unit Numbers [12/09/1998]

How do you prove this statement: For every prime number there exists a repeated unit number that is a multiple of that prime.

Teaching Elementary Concepts [04/04/1997]

How can I teach rational counting, prime and composite numbers, and square roots at a grade-school level?

Why Prime Numbers? [10/21/2001]

What are prime numbers used for in math?

Why Study Prime and Composite Numbers? [01/25/2001]

My husband and I wonder why this is taught in school at all. Who uses this in the real world? Why does someone need to know whether a number is a prime number or not?

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