## Michael797 3 years ago Are 0 & 1 Prime or Composite numbers?

1. Akshay_Budhkar

Neither 1 or 0 are prime or composite.

2. Michael797

Well what would I put for this problem then? : The zip code of a location consists of five digits chosen from the set D shown below. D = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9} The set M represents the digits in one of the zip codes for Miami. M = {3, 3, 1, 9, 0} The set C represents the digits in one of the zip codes for Cooper City. C = {3, 3, 3, 3, 0} How many prime numbers are in the set M(U)C ?

3. Michael797

I know 3 is prime..so thats 1, then 9 is not prime, and i had no idea what to do about 1 & 0

4. Akshay_Budhkar

Yea, 1 and 0 are not prime :) The reason been One is neither a prime nor a composite number. A prime number is one with exactly two positive divisors, itself and one. One has only one positive divisor. It cannot be written as a product of two factors, neither of which is itself, so one is also not composite. It falls in a class of numbers called units. These are the numbers whose reciprocals are also whole numbers. Zero is not a prime or a composite number either. Zero has an infinite number of divisors (any nonzero whole number divides zero). It cannot be written as a product of two factors, neither of which is itself, so zero is also not composite. It falls in a class of numbers called zero-divisors. These are numbers such that, when multiplied by some nonzero number, the product is zero. So your answer is just 1 prime number

5. Michael797

Thank you! That question really confused me :)