3-6 Multiplying Three Numbers

These symbols ( ) are parentheses. You always do what is inside of the parentheses ( ) first.

For example:

You add (3 + 2) + 4 like this:  (3 + 2) + 4 = (5) + 4 = 9

You add 3 + (4 + 2) like this:  3 + (4 + 2) = 3 + (6) = 9

Whether you put the 3 + 2 in parentheses or the 4 + 2 in the parentheses, the sum will be the same. No matter how you group the addends using parentheses, the sum will always be the same.

You can also multiply three or more numbers (factors) when using parentheses.

Multiply (2 X 3 ) X 5 like this: (2 X 3) X 5 = (6) X 5 = 30

Multiply 2 X (3 X 5) like this: 2 X (3 X 5) = 2 X (15) = 30

The product is always the same no matter how you group the factors.

Fill in the correct products and factors.

(3 X 2) X 2 =	4 X (2 X 5) =	(1 X 4) X 5 =
3 X (2 X 2) =	(4 X 2) X 5 =	1 X (4 X 5) =
5 X (3 X 3) =	(7 X 2) X 1 =	8 X (2 X 3) =
(6 X 3) X 1 =	9 X (3 X 2) =	(4 X 2) X 9 =
(4 X 2) X = 40	(3 X 1) X = 9	(2 X 5) X = 20
(1 X 5) X = 25	(2 X 2) X = 32	(2 X4) X = 32
X (3 X 2) = 30	X (2 X 4) = 48	X (6 X 1) = 42
X (1 X 5) = 45	X (5 X 2) = 60	X (3 X 3) = 27