3 is the smallest odd prime number. 3 = 1 x 3. Its only factors are 1 and 3. Prime factorization: none.
How do we know that 3 is a prime number? The square root of 3 is an irrational number approximately equal to 1.73. If 3 were not a prime number, then it would be divisible by at least one prime number less than or equal to 1.73. Since there are no prime numbers less than or equal to 1.73, we know 3 is a prime number.
When 3 is a clue in the FIND THE FACTOR puzzles, the factors are always 1 and 3.
Click on this link, 10 factors 2013-11-04, to get printable copies of the puzzles below and last Monday’s answers. To solve the puzzles, place the numbers 1 – 10 in both the top row and the first column so that those numbers are the factors of the given clues. Obviously level 6 is more difficult to solve than level 1.