**Establish whether a number up to 100 is prime and recall prime numbers to 19**

Prime digits printable sheet (PDF)

**Investigation: Prime digits**

Mike has written down all of the prime numbers between 1 and 100.
Why do you think these digits are used the most and the least? |

Answer

The least used digit is 0 which isn’t used. 6 and 8 are used twice (61 and 67; 83 and 89)

The most used digits are 1 and 3

1 – 11, 13, 17, 19, 31, 41, 61, 71

3 – 3, 13, 23, 31, 37, 43, 53, 83.

The understanding of odd and even, use of the digit in each times table (e.g. x5) give a reason as to why they are used the most/least.