Lesson 4 – Multiplying Two Digits Numbers By One Digit Number

Objective:

• At the end of this lesson, students should be able to multiply two digits numbers by one digit numbers.

Example 1

Multiply 21 by 2

Solution

Always start your multiplication from the right hand side. 2 times 1 is 2. Write 2 under the units column.

Multiply 2 by the 2 in the Tens column. That is 2 x 2 = 4

Write 4 in the Tens Column.

So 21 x 2 = 42.

Example 2

Multiply 81 by 3

Solution

3 x 1 = 3, write the 3 in the units column.

3 x 8 = 24, 3 times 8 Tens is 24 Tens.

24 Tens is 2 Hundreds and 4 Tens. Write 4 in the Tens column and 2 in the Hundreds column.

81 x 3 = 243

Example 3

Multiply 46 by 2

Solution

Multiply all units: 2 x 6 = 12.

Write 2 under the units column and carry 1 to the Tens column.

Multiply all tens: 2 x 4 = 8, add the 1 you carried to the Tens column to 8 to get 9 tens. Write 9 in the tens column.

Your answer is 92 because 46 x 2 = 92