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Selected answers to common questions:
- 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
- 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
- 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
- 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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