Multiplication Strategies and Techniques

The video tutorial explains how to multiply large numbers by breaking them into smaller, more manageable parts. It demonstrates this technique with examples, such as multiplying 40 by 70 and 90 by 30, by decomposing the numbers into factors of 10. The tutorial emphasizes the flexibility of multiplication order and the ease of multiplying by 10, which involves adding zeros. This method simplifies complex multiplication problems, making them easier to solve.

What is the initial method suggested for multiplying 40 by 70?

• Using a calculator

• Dividing 70 by 40

• Subtracting 40 from 70

• Listing 70 forty times and adding

Why is multiplying by 10 considered easy in the video?

• It uses division

• It requires subtraction

• It involves complex calculations

• It involves adding a zero

How are the numbers 40 and 70 decomposed for easier multiplication?

• 2 times 20 and 3 times 30

• 10 times 4 and 10 times 7

• 4 times 10 and 7 times 10

• 5 times 8 and 6 times 12

What is the result of multiplying 4 by 7 in the calculation?

• 49

• 28

• 35

• 42

What is the final result of 40 times 70 using the decomposition method?

• 7000

• 2800

• 4000

• 1400

What is the first step in multiplying 90 by 30?

• Dividing 90 by 30

• Subtracting 30 from 90

• Decomposing into 9 times 10 and 3 times 10

• Adding 90 and 30

What is the result of multiplying 9 by 3 in the new example?

• 36

• 18

• 45

• 27

How many zeros are added when multiplying by two tens?

• None

• One

• Two

• Three

What is the final result of 90 times 30 using the decomposition method?

• 3000

• 3600

• 2700

• 1800

What is the key concept reinforced by the end of the video?

• Addition is faster than multiplication

• Multiplying by tens simplifies calculations

• Subtraction is more efficient

• Division is the best method