How to Use One Multiplication Fact to Complete Another One

A Step-by-step Guide to Using One Multiplication Fact to Complete Another One

Sure, using one multiplication fact to complete another is a useful strategy when learning multiplication. It is based on the properties of multiplication like the Commutative, Associative, and Distributive properties. Here is a step-by-step guide:

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Step 1: Identify Known Multiplication Facts

First, you’ll want to start with a multiplication fact that you already know. For example, let’s say you know that \(5 x 4 = 20\).

Step 2: Using the Commutative Property

The Commutative Property states that you can switch the order of the factors and the product remains the same. So if you know that \(5 x 4 = 20\), you also know that \(4 x 5 = 20\).

Step 3: Using the Associative Property

The Associative Property allows us to change the grouping of numbers in a multiplication problem without changing the product. For example, if you know that \(2 x 4 = 8\), you can use this to find out what \(4 x 4\) is. Because 4 is the same as \(2 x 2\), you can group the problem like this: \(2 x (2 x 4)\). Then, using the fact you already know \((2 x 4 = 8)\), you can simplify it to \(8 x 2 = 16\).

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Step 4: Using the Distributive Property

The Distributive Property allows you to break down a larger multiplication problem into smaller, more manageable parts. For example, if you want to figure out what \(6 x 7\) is, but you only know up to your 5 times table, you can break 6 down into \(5 + 1\). Then, use the Distributive Property to rewrite the problem as \((5 x 7) + (1 x 7)\). If you know that \(5 x 7 = 35\) and \(1 x 7 = 7\), you can add these together to get 42.

So, by using these properties of multiplication, you can leverage multiplication facts you already know to figure out new multiplication facts. This is a great way to build your understanding and fluency with multiplication. For education statistics and research, visit the National Center for Education Statistics.

The Best Math Books for Elementary Students For education statistics and research, visit the National Center for Education Statistics.

A Step-by-step Guide to Using One Multiplication Fact to Complete Another One

Sure, using one multiplication fact to complete another is a useful strategy when learning multiplication. It is based on the properties of multiplication like the Commutative, Associative, and Distributive properties. Here is a step-by-step guide:

The Absolute Best Book for 4th Grade Students

Step 1: Identify Known Multiplication Facts

First, you’ll want to start with a multiplication fact that you already know. For example, let’s say you know that \(5 x 4 = 20\).

Step 2: Using the Commutative Property

The Commutative Property states that you can switch the order of the factors and the product remains the same. So if you know that \(5 x 4 = 20\), you also know that \(4 x 5 = 20\).

Step 3: Using the Associative Property

The Associative Property allows us to change the grouping of numbers in a multiplication problem without changing the product. For example, if you know that \(2 x 4 = 8\), you can use this to find out what \(4 x 4\) is. Because 4 is the same as \(2 x 2\), you can group the problem like this: \(2 x (2 x 4)\). Then, using the fact you already know \((2 x 4 = 8)\), you can simplify it to \(8 x 2 = 16\).

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Basic Mathematics for Beginners The Ultimate Step by Step Guide and A Comprehensive Basic Math Refresher

Download

$27.99 Original price was: $27.99.$17.99Current price is: $17.99.

Step 4: Using the Distributive Property

The Distributive Property allows you to break down a larger multiplication problem into smaller, more manageable parts. For example, if you want to figure out what \(6 x 7\) is, but you only know up to your 5 times table, you can break 6 down into \(5 + 1\). Then, use the Distributive Property to rewrite the problem as \((5 x 7) + (1 x 7)\). If you know that \(5 x 7 = 35\) and \(1 x 7 = 7\), you can add these together to get 42.

So, by using these properties of multiplication, you can leverage multiplication facts you already know to figure out new multiplication facts. This is a great way to build your understanding and fluency with multiplication. For education statistics and research, visit the National Center for Education Statistics.

The Best Math Books for Elementary Students For education statistics and research, visit the National Center for Education Statistics.

Deriving Related Facts Using Multiplication Properties

When you know one multiplication fact, you can generate many others using doubling, halving, and the distributive property. This technique is fundamental to building computational fluency.

Doubling Strategy

If you know \(3 \times 4 = 12\), you can find \(3 \times 8\) by doubling:

Since 8 is twice 4, \(3 \times 8 = 3 \times (2 \times 4) = 2 \times (3 \times 4) = 2 \times 12 = 24\)

Halving Strategy

If you know \(6 \times 8 = 48\), you can find \(6 \times 4\):

Since 4 is half of 8, \(6 \times 4 = 6 \times \frac{8}{2} = \frac{6 \times 8}{2} = \frac{48}{2} = 24\)

Distributive Property Method

If you know \(5 \times 6 = 30\), you can find \(5 \times 7\):

\(5 \times 7 = 5 \times (6 + 1) = (5 \times 6) + (5 \times 1) = 30 + 5 = 35\)

Worked Example 1: Building from 3 × 5

Given: \(3 \times 5 = 15\)

Find: \(3 \times 10\), \(6 \times 5\), \(3 \times 6\)

Solution:

• \(3 \times 10 = 3 \times (2 \times 5) = 2 \times (3 \times 5) = 2 \times 15 = 30\)
• \(6 \times 5 = (2 \times 3) \times 5 = 2 \times (3 \times 5) = 2 \times 15 = 30\)
• \(3 \times 6 = 3 \times (5 + 1) = 15 + 3 = 18\)

Worked Example 2: Chain of Derivations

Given: \(4 \times 7 = 28\)

Find: \(4 \times 14\), \(8 \times 7\), \(4 \times 6\), \(2 \times 7\)

Solution:

• \(4 \times 14 = 4 \times (2 \times 7) = 2 \times (4 \times 7) = 2 \times 28 = 56\) [doubling]
• \(8 \times 7 = (2 \times 4) \times 7 = 2 \times (4 \times 7) = 56\) [doubling]
• \(4 \times 6 = 4 \times (7 – 1) = (4 \times 7) – 4 = 28 – 4 = 24\) [distributive]
• \(2 \times 7 = \frac{4 \times 7}{2} = \frac{28}{2} = 14\) [halving]

Worked Example 3: Using the Associative Property

Given: \(2 \times 8 = 16\)

Find: \(6 \times 8\) (using intermediate facts)

Solution:

\(6 \times 8 = (3 \times 2) \times 8 = 3 \times (2 \times 8) = 3 \times 16 = 48\)

Breaking Down Complex Facts

Given: \(7 \times 8 = 56\)

Find: \(7 \times 9\) using the previous fact

Solution:

\(7 \times 9 = 7 \times (8 + 1) = (7 \times 8) + 7 = 56 + 7 = 63\)

Multiplication Table Patterns

When you look at a multiplication table, patterns emerge from these derivation strategies:

• Each row doubles as you move right (e.g., 3×4=12, 3×8=24, 3×16=48)
• Products are symmetric: \(a \times b = b \times a\)
• Adjacent facts differ by one multiplicand: \(5 \times 7 = 35\) and \(5 \times 8 = 40\) differ by 5

Real-World Application

A baker knows that 3 batches of cookies require 12 eggs. To quickly determine how many eggs are needed for:

• 6 batches (double): \(2 \times 12 = 24\) eggs
• 1.5 batches (half): \(\frac{12}{2} = 6\) eggs
• 4 batches: \(12 + (1 \times 12) = 12 + 12 = 24\) eggs, or using another method: \(3 \times 4 \times 1 + 1 \times 12 = 16\) eggs

Practice Problems

1. If \(6 \times 9 = 54\), find \(6 \times 18\) and \(12 \times 9\).
2. If \(5 \times 4 = 20\), find \(5 \times 5\) using the distributive property.
3. If \(8 \times 7 = 56\), find \(4 \times 7\) by halving.
4. If \(9 \times 6 = 54\), find \(9 \times 12\), \(9 \times 5\), and \(18 \times 6\).
5. Using \(7 \times 8 = 56\), derive three other multiplication facts.

Mental Math Mastery

These derivation strategies form the foundation of mental arithmetic. By understanding how multiplication facts relate to each other, you can solve problems without memorizing every single fact. For deeper understanding of multiplication concepts, explore using properties to write equivalent expressions and the distributive property to factor variable expressions.

Connecting to Algebra

These same properties work with variables and algebraic expressions. The ability to see \(3x \times 2 = 6x\) comes directly from understanding \(3 \times 2 = 6\).

A Step-by-step Guide to Using One Multiplication Fact to Complete Another One

Sure, using one multiplication fact to complete another is a useful strategy when learning multiplication. It is based on the properties of multiplication like the Commutative, Associative, and Distributive properties. Here is a step-by-step guide:

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Step 1: Identify Known Multiplication Facts

First, you’ll want to start with a multiplication fact that you already know. For example, let’s say you know that \(5 x 4 = 20\).

Step 2: Using the Commutative Property

The Commutative Property states that you can switch the order of the factors and the product remains the same. So if you know that \(5 x 4 = 20\), you also know that \(4 x 5 = 20\).

Step 3: Using the Associative Property

The Associative Property allows us to change the grouping of numbers in a multiplication problem without changing the product. For example, if you know that \(2 x 4 = 8\), you can use this to find out what \(4 x 4\) is. Because 4 is the same as \(2 x 2\), you can group the problem like this: \(2 x (2 x 4)\). Then, using the fact you already know \((2 x 4 = 8)\), you can simplify it to \(8 x 2 = 16\).

A Perfect Book for Grade 4 Math Word Problems!

Basic Mathematics for Beginners The Ultimate Step by Step Guide and A Comprehensive Basic Math Refresher

Download

$27.99 Original price was: $27.99.$17.99Current price is: $17.99.

Step 4: Using the Distributive Property

The Distributive Property allows you to break down a larger multiplication problem into smaller, more manageable parts. For example, if you want to figure out what \(6 x 7\) is, but you only know up to your 5 times table, you can break 6 down into \(5 + 1\). Then, use the Distributive Property to rewrite the problem as \((5 x 7) + (1 x 7)\). If you know that \(5 x 7 = 35\) and \(1 x 7 = 7\), you can add these together to get 42.

So, by using these properties of multiplication, you can leverage multiplication facts you already know to figure out new multiplication facts. This is a great way to build your understanding and fluency with multiplication. For education statistics and research, visit the National Center for Education Statistics.

The Best Math Books for Elementary Students For education statistics and research, visit the National Center for Education Statistics.

A Step-by-step Guide to Using One Multiplication Fact to Complete Another One

Sure, using one multiplication fact to complete another is a useful strategy when learning multiplication. It is based on the properties of multiplication like the Commutative, Associative, and Distributive properties. Here is a step-by-step guide:

The Absolute Best Book for 4th Grade Students

Step 1: Identify Known Multiplication Facts

First, you’ll want to start with a multiplication fact that you already know. For example, let’s say you know that \(5 x 4 = 20\).

Step 2: Using the Commutative Property

The Commutative Property states that you can switch the order of the factors and the product remains the same. So if you know that \(5 x 4 = 20\), you also know that \(4 x 5 = 20\).

Step 3: Using the Associative Property

The Associative Property allows us to change the grouping of numbers in a multiplication problem without changing the product. For example, if you know that \(2 x 4 = 8\), you can use this to find out what \(4 x 4\) is. Because 4 is the same as \(2 x 2\), you can group the problem like this: \(2 x (2 x 4)\). Then, using the fact you already know \((2 x 4 = 8)\), you can simplify it to \(8 x 2 = 16\).

A Perfect Book for Grade 4 Math Word Problems!

Basic Mathematics for Beginners The Ultimate Step by Step Guide and A Comprehensive Basic Math Refresher

Download

$27.99 Original price was: $27.99.$17.99Current price is: $17.99.

Step 4: Using the Distributive Property

The Distributive Property allows you to break down a larger multiplication problem into smaller, more manageable parts. For example, if you want to figure out what \(6 x 7\) is, but you only know up to your 5 times table, you can break 6 down into \(5 + 1\). Then, use the Distributive Property to rewrite the problem as \((5 x 7) + (1 x 7)\). If you know that \(5 x 7 = 35\) and \(1 x 7 = 7\), you can add these together to get 42.

So, by using these properties of multiplication, you can leverage multiplication facts you already know to figure out new multiplication facts. This is a great way to build your understanding and fluency with multiplication. For education statistics and research, visit the National Center for Education Statistics.

The Best Math Books for Elementary Students For education statistics and research, visit the National Center for Education Statistics.

Deriving Related Facts Using Multiplication Properties

When you know one multiplication fact, you can generate many others using doubling, halving, and the distributive property. This technique is fundamental to building computational fluency.

Doubling Strategy

If you know \(3 \times 4 = 12\), you can find \(3 \times 8\) by doubling:

Since 8 is twice 4, \(3 \times 8 = 3 \times (2 \times 4) = 2 \times (3 \times 4) = 2 \times 12 = 24\)

Halving Strategy

If you know \(6 \times 8 = 48\), you can find \(6 \times 4\):

Since 4 is half of 8, \(6 \times 4 = 6 \times \frac{8}{2} = \frac{6 \times 8}{2} = \frac{48}{2} = 24\)

Distributive Property Method

If you know \(5 \times 6 = 30\), you can find \(5 \times 7\):

\(5 \times 7 = 5 \times (6 + 1) = (5 \times 6) + (5 \times 1) = 30 + 5 = 35\)

Worked Example 1: Building from 3 × 5

Given: \(3 \times 5 = 15\)

Find: \(3 \times 10\), \(6 \times 5\), \(3 \times 6\)

Solution:

• \(3 \times 10 = 3 \times (2 \times 5) = 2 \times (3 \times 5) = 2 \times 15 = 30\)
• \(6 \times 5 = (2 \times 3) \times 5 = 2 \times (3 \times 5) = 2 \times 15 = 30\)
• \(3 \times 6 = 3 \times (5 + 1) = 15 + 3 = 18\)

Worked Example 2: Chain of Derivations

Given: \(4 \times 7 = 28\)

Find: \(4 \times 14\), \(8 \times 7\), \(4 \times 6\), \(2 \times 7\)

Solution:

• \(4 \times 14 = 4 \times (2 \times 7) = 2 \times (4 \times 7) = 2 \times 28 = 56\) [doubling]
• \(8 \times 7 = (2 \times 4) \times 7 = 2 \times (4 \times 7) = 56\) [doubling]
• \(4 \times 6 = 4 \times (7 – 1) = (4 \times 7) – 4 = 28 – 4 = 24\) [distributive]
• \(2 \times 7 = \frac{4 \times 7}{2} = \frac{28}{2} = 14\) [halving]

Worked Example 3: Using the Associative Property

Given: \(2 \times 8 = 16\)

Find: \(6 \times 8\) (using intermediate facts)

Solution:

\(6 \times 8 = (3 \times 2) \times 8 = 3 \times (2 \times 8) = 3 \times 16 = 48\)

Breaking Down Complex Facts

Given: \(7 \times 8 = 56\)

Find: \(7 \times 9\) using the previous fact

Solution:

\(7 \times 9 = 7 \times (8 + 1) = (7 \times 8) + 7 = 56 + 7 = 63\)

Multiplication Table Patterns

When you look at a multiplication table, patterns emerge from these derivation strategies:

• Each row doubles as you move right (e.g., 3×4=12, 3×8=24, 3×16=48)
• Products are symmetric: \(a \times b = b \times a\)
• Adjacent facts differ by one multiplicand: \(5 \times 7 = 35\) and \(5 \times 8 = 40\) differ by 5

Real-World Application

A baker knows that 3 batches of cookies require 12 eggs. To quickly determine how many eggs are needed for:

• 6 batches (double): \(2 \times 12 = 24\) eggs
• 1.5 batches (half): \(\frac{12}{2} = 6\) eggs
• 4 batches: \(12 + (1 \times 12) = 12 + 12 = 24\) eggs, or using another method: \(3 \times 4 \times 1 + 1 \times 12 = 16\) eggs

Practice Problems

1. If \(6 \times 9 = 54\), find \(6 \times 18\) and \(12 \times 9\).
2. If \(5 \times 4 = 20\), find \(5 \times 5\) using the distributive property.
3. If \(8 \times 7 = 56\), find \(4 \times 7\) by halving.
4. If \(9 \times 6 = 54\), find \(9 \times 12\), \(9 \times 5\), and \(18 \times 6\).
5. Using \(7 \times 8 = 56\), derive three other multiplication facts.

Mental Math Mastery

These derivation strategies form the foundation of mental arithmetic. By understanding how multiplication facts relate to each other, you can solve problems without memorizing every single fact. For deeper understanding of multiplication concepts, explore using properties to write equivalent expressions and the distributive property to factor variable expressions.

Connecting to Algebra

These same properties work with variables and algebraic expressions. The ability to see \(3x \times 2 = 6x\) comes directly from understanding \(3 \times 2 = 6\).

Deriving Related Facts Using Multiplication Properties

When you know one multiplication fact, you can generate many others using doubling, halving, and the distributive property. This technique is fundamental to building computational fluency.

Doubling Strategy

If you know \(3 \times 4 = 12\), you can find \(3 \times 8\) by doubling:

Since 8 is twice 4, \(3 \times 8 = 3 \times (2 \times 4) = 2 \times (3 \times 4) = 2 \times 12 = 24\)

Halving Strategy

If you know \(6 \times 8 = 48\), you can find \(6 \times 4\):

Since 4 is half of 8, \(6 \times 4 = 6 \times \frac{8}{2} = \frac{6 \times 8}{2} = \frac{48}{2} = 24\)

Distributive Property Method

If you know \(5 \times 6 = 30\), you can find \(5 \times 7\):

\(5 \times 7 = 5 \times (6 + 1) = (5 \times 6) + (5 \times 1) = 30 + 5 = 35\)

Worked Example 1: Building from 3 × 5

Given: \(3 \times 5 = 15\)

Find: \(3 \times 10\), \(6 \times 5\), \(3 \times 6\)

Solution:

• \(3 \times 10 = 3 \times (2 \times 5) = 2 \times (3 \times 5) = 2 \times 15 = 30\)
• \(6 \times 5 = (2 \times 3) \times 5 = 2 \times (3 \times 5) = 2 \times 15 = 30\)
• \(3 \times 6 = 3 \times (5 + 1) = 15 + 3 = 18\)

Worked Example 2: Chain of Derivations

Given: \(4 \times 7 = 28\)

Find: \(4 \times 14\), \(8 \times 7\), \(4 \times 6\), \(2 \times 7\)

Solution:

• \(4 \times 14 = 4 \times (2 \times 7) = 2 \times (4 \times 7) = 2 \times 28 = 56\) [doubling]
• \(8 \times 7 = (2 \times 4) \times 7 = 2 \times (4 \times 7) = 56\) [doubling]
• \(4 \times 6 = 4 \times (7 – 1) = (4 \times 7) – 4 = 28 – 4 = 24\) [distributive]
• \(2 \times 7 = \frac{4 \times 7}{2} = \frac{28}{2} = 14\) [halving]

Worked Example 3: Using the Associative Property

Given: \(2 \times 8 = 16\)

Find: \(6 \times 8\) (using intermediate facts)

Solution:

\(6 \times 8 = (3 \times 2) \times 8 = 3 \times (2 \times 8) = 3 \times 16 = 48\)

Breaking Down Complex Facts

Given: \(7 \times 8 = 56\)

Find: \(7 \times 9\) using the previous fact

Solution:

\(7 \times 9 = 7 \times (8 + 1) = (7 \times 8) + 7 = 56 + 7 = 63\)

Multiplication Table Patterns

When you look at a multiplication table, patterns emerge from these derivation strategies:

• Each row doubles as you move right (e.g., 3×4=12, 3×8=24, 3×16=48)
• Products are symmetric: \(a \times b = b \times a\)
• Adjacent facts differ by one multiplicand: \(5 \times 7 = 35\) and \(5 \times 8 = 40\) differ by 5

Real-World Application

A baker knows that 3 batches of cookies require 12 eggs. To quickly determine how many eggs are needed for:

• 6 batches (double): \(2 \times 12 = 24\) eggs
• 1.5 batches (half): \(\frac{12}{2} = 6\) eggs
• 4 batches: \(12 + (1 \times 12) = 12 + 12 = 24\) eggs, or using another method: \(3 \times 4 \times 1 + 1 \times 12 = 16\) eggs

Practice Problems

1. If \(6 \times 9 = 54\), find \(6 \times 18\) and \(12 \times 9\).
2. If \(5 \times 4 = 20\), find \(5 \times 5\) using the distributive property.
3. If \(8 \times 7 = 56\), find \(4 \times 7\) by halving.
4. If \(9 \times 6 = 54\), find \(9 \times 12\), \(9 \times 5\), and \(18 \times 6\).
5. Using \(7 \times 8 = 56\), derive three other multiplication facts.

Mental Math Mastery

These derivation strategies form the foundation of mental arithmetic. By understanding how multiplication facts relate to each other, you can solve problems without memorizing every single fact. For deeper understanding of multiplication concepts, explore using properties to write equivalent expressions and the distributive property to factor variable expressions.

Connecting to Algebra

These same properties work with variables and algebraic expressions. The ability to see \(3x \times 2 = 6x\) comes directly from understanding \(3 \times 2 = 6\).