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Chapter 1 Whole Numbers 1-6 Multiplying Whole Numbers Multiplication is souped-up addition. Suppose you have four cartons of eggs and each carton contains a dozen (12) eggs. How many eggs do you have here? - You could open all the cartons and count each egg individually: one egg, two eggs, three eggs, ... and so on.
- Or you can add four 12s: 12 eggs + 12 eggs + 12 eggs + 12 eggs = 48 eggs
- Or you can multiply: 12 eggs/carton times 4 cartons = 48 eggs
It is clearly simpler and faster to use the multiplication approach. NOTE: Multiplication is repeated addition. | Here is the standard multiplication table. It shows the results of adding all possible combinations of two digits, from 0 x 0 = 0 through 9 x 9 = 81. Study the table carefully, and see if you can figure out how it works. 
Multiplication Table | | | Multiplication facts | Definitions The multiplication sign (x) indicates the multiplication operation. | Multiplication problems are sometimes written in a horizontal form such as: 3 x 5 = 15 This form is called a number sentence. It is read as, "Three times five equals fifteen." - The multiplication sign (x) indicates the multiplication operation.
- The equal sign (=) expresses the equality of the two parts of the sentence.
|  | Examples | 1. 1 x 2 = 2 | 2. 3 x 6 = 18 | 3. 4 x 0 = 0 | 4. 5 x 7 = 35 | 5. 6 x 8 = 48 | There are three different symbols for indicating the multiplication operation: - Factors separated by the x multiplication symbol. Example: 4 x 2 = 8
- Factors separated by a dot. Example: 4 � 2 = 8
- Each factor enclosed in paretheses with no symbol between. Example: (4)(2) = 8
Multiplying Larger Numbers 
Notes - Any value multiplied by one is equal to the original value.
| Example: 5 x 1 = 5 | - Zero multiplied by any value is equal to zero.
| Example: 0 x 2 = 0 | - Factors may be multiplied in any order. (This is known as the commutative law of multiplication)
| Example: 3 x 2 = 6 and 2 x 3 = 6
In other words, 3 x 2 = 2 x 3 | |
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