In this column I will explain some of the frequently asked questions that we receive as tutors here at CAMI. The topic for this issue will be numbers!

Today, we will focus on a very special group of numbers that we call whole numbers. Numbers like 0, 1, 2, 3, 4, 5… (and so on) are all whole numbers. These are the numbers you might often use for counting or doing all kinds of arithmetic such as multiplication and division. You may want to count your toes and see that the total number of toes you have is a whole number!!

**Example**: Whole Numbers

There is a special type of whole number called an *integer.* Integers can be *positive* like 132 or *negative* like -5. Zero can also be an integer. Just to be confusing, *some* people say that whole numbers can also be negative, so that would make them exactly the same as integers. And sometimes people say that zero is not a whole number. So there you go, not everybody agrees on a simple thing!

**Example**: Integers

Whole numbers and integers can be *odd* like 7, 9, 13, 17 or *even* like 2, 4, 8 or 16. What makes odd numbers different from an even number is that even numbers are multiples of 2. You can think of your 2 times tables for all multiples of 2.

2 x 1 = 2

2 x 2 = 4

2 x 3 = 6

If a number is in the 2 times tables, then it is a multiple of 2. If it is a multiple of 2 then it is even! For example, 8 is an even number because 4 x 2 gives you 8! So 8 is a multiple 2. Another example of an even number is the number 10. Why? Because 2 x 5 = 10!

Is 5 an even number? The answer is in fact no. 5 is not a multiple of 2. Another way of looking at this is that any number that is not even, that is not a multiple of two, is an odd number.

**Exercises:**

- Is 12 an even number?
- Is 7 an odd or an even number?
- Which of these numbers are odd?

2, 3, 11, 8, 9

**Answers:**

- Yes
- Odd
- 3, 11, 9