As shown in the last lesson, Adding and Subtracting Negative Numbers, the next step is to multiply and divide them. Luckily, this is even easier!
Multiplication (Go to Division) Let's take a look at a normal multiplication problem:
Why does it equal 12? You can look at it one of two ways:
1. The number 3 added to itself 4 times. (3 + 3 + 3 + 3 = 12)
2. The number 4 added to itself 4 times. (4 + 4 + 4 = 12)
What if you had a negative 3 in the above problem? It could be written as (3 + 3 + 3 + 3). If you read our previous lesson, you know that this can be rewritten as: 3  3  3  3, which equals 12.
Important Rules for Multiplication (and Division) with Negative Numbers: 
If there is an EVEN amount (or 0) of negative numbers in the problem, the answer will be a POSITIVE. A negative times a negative is a positive. 
If there is a ODD amount of negative signs in the problem, the answer will be a NEGATIVE number. A positive times a negative is a negative number. 
That's it. Nothing else changes. Simply multiply the numbers, count up the negative numbers, and depending on how many there are, you may need to add a negative sign in front of your answer. Yes, that's all there is to it!
Here are some examples to try. (Answers below)
1. 4 x 5
2. 4 x 6
3. 2 x 3 x 4
4. 3 x 5 x 1
5. 6 x 2 x 3
Answers:
1. 20.
2. 24.
3. 24.
4. 15.
5. 36.
Division
We'll try to keep this short:
Follow the exact same rules as for multiplication (above), but divide instead. The only thing to remember:
An even amount of negative signs and the answer will be positive; an odd amount and the answer is negative. 
Try some:
1. 8 ÷ 4
2. 12 ÷ 3
3. 4 ÷ 2
4. 15 ÷ 5
5. (16 ÷ 4) ÷ 2
(Hint: Do the calculation in the parenthesis first,
and then finish with the last divide.)
Answers:
1. 2
2. 4
3. 2
4. 3
5. 2
Nothing to it!
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