KS2 Primary Maths Age 13-17 - Calculations: Written Multiplication - Explained

The video tutorial explains the process of long multiplication using the example of 785 multiplied by 23. It emphasizes the importance of understanding basic arithmetic rules and demonstrates the step-by-step multiplication of 785 by 3 and 20. The tutorial highlights the significance of placing a zero when multiplying by tens and provides guidance on adding the results. It concludes with an explanation of how marks are allocated for correct answers and methods, stressing the importance of including the zero for method marks.

What are the four basic arithmetic operations essential for solving long multiplication problems?

• Addition, Multiplication, Division, Square Root

• Addition, Subtraction, Division, Modulus

• Addition, Subtraction, Multiplication, Exponentiation

• Addition, Subtraction, Multiplication, Division

When multiplying 785 by 3, what is the result of 3 times 5?

• 20

• 10

• 25

• 15

In the multiplication of 785 by 3, what number do you carry over after multiplying 3 by 8?

• 1

• 5

• 2

• 3

Why is it important to place a zero in the units column when multiplying by 20?

• To avoid arithmetic mistakes

• To get the method mark

• To ensure the correct placement of digits

• To make the multiplication easier

What is the final result of the multiplication 785 * 23?

• 18055

• 17055

• 16055

• 19055