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We need to know a different ways to multiply...you might be asked to use a specific method to get your answer in a test like the PARCC. They are all related and all contain partial products.

The Expanded Algorithm 1

The Area Model

https://learnzillion.com/lessons/23-solve-1-by-1-digit-multiplication-problems-using-area-model

https://learnzillion.com/lessons/24-solve-2-by-2-digit-multiplication-problems-using-area-model

The Partial Product Method

https://learnzillion.com/lessons/21-solve-1-by-2-digit-multiplication-problems-using-partial-products

https://learnzillion.com/lessons/22-solve-2-by-2-digit-multiplication-problems-using-partial-products

Using the Distributive Property

Remember the Properties of Multiplication (you NEED to know these)

Commutative Property:

When two numbers are multiplied together, the product is the same regardless of the order of the multiplicands.

For example 4 x 2 = 2 x 4

Associative Property:

When three or more numbers are multiplied, the product is the same regardless of the grouping of the factors.

For example (2 x 3) x 4 = 2 x (3 x4)

Multiplicative Identity Property:

The product of any number and one is that number.

For example 5 x 1 = 5.

Distributive Property:

The sum of two numbers times a third number is equal to the sum of each addend times the third number.

For example 4 x (6 + 3) = 4 x 6 + 4 x 3

Below are some fast multiplication tricks you can use in mental math...you might use these in a contest link the Math Olympiad.

Multiplication Tricks (you do NOT need to know this)