An alternative method to multiply 2-digit and 3-digit numbers by a 1-digit number without using a calculator

Many students struggle with learning, remembering and retrieving multiplication facts when performing multiplication computations. The struggle gets greater when working with big numbers.

Ever wondered if there is an alternative way to make the multiplication task easier for them?

Let’s consider a different approach that can help the students produce the same result – ADDITION
Addition involves only two skills – adding on and renaming.

Since students learn best when things are made visual and hands-on, begin by getting the students to make their own set of multiplication table strips and empower them to get their multiplication computations correct whether they are multiplying 1-digit numbers or bigger numbers.

Here’s how:

  1. Make vertical strips of times tables 1-9 as shown in the table below. In the multiples of each times table, draw a diagonal to separate the digits in each multiple Screenshot-2023-03-01-163852
  2. For a multiple less than ten, write the digit ‘0’ before the number.
  3. Next, make a red strip of the multiplier numbers 1-9
  4. You can multiply any number by the multiplier number.
  5. Let’s try to multiply a 2-digit number with renaming → 45 x 7
  6. Place the 4 and 5 times table strips beside, to the right of Row 7 of the multiplier strip.
  7. To get the answer for 45 x 7, add the digits in the same diagonal columns from the right to the left corresponding to Row 7. The middle diagonal column containing the numbers 8 and 3 are to be added
    → 8 + 3 = 11. 1 ten is brought over to the left column and added to 2, giving 3.
    The answer for 45 x 7 is therefore 315.

Here are some examples to help you to understand better:

1. Multiply a single digit number by 6:

Eg. 7 x 6

Place the 7 times table strip beside the multiplier 6
Read the numbers corresponding to row 6 – So 6 x 7 = 42

2. Multiply a 2- digit number without renaming:

Eg.
57 x 2
57 x 4
57 x 6
57 x 8

Place the 5 and 7 times table strips beside the multiplier strip.

Read the numbers corresponding to:
Row 2 – 57 x 2 = 114
Row 4 – 57 x 4 = 228
Row 6 – 57 x 6 = 342
Row 8 – 57 x 8 = 456

3. Multiply a 2- digit number with renaming:

Eg.
69 x 3
69 x 6
69 x 8
69 x 9

Place the 6 and 9 times table strips beside the multiplier strip.

Read the numbers corresponding to:
Row 3 – 69 x 3 = 207
Row 6 – 69 x 6 = 41
Row 8 – 69 x 8 = 552
Row 9 – 69 x 9 = 621

4. Multiply a 3-digit number with and without renaming:

Eg.
679 x 2
679 x 4
679 x 7
679 x 8
679 x 9

Place the 6, 7 and 9 times table strips beside the multiplier strip.

Read the numbers corresponding to:
Row 2 – 679 x 3 = 1358
Row 4 – 679 x 6 = 2716
Row 7 – 679 x 8 = 4753
Row 8 – 679 x 9 = 5432
Row 9 – 679 x 9 = 611

Dear Teachers,

Now, isn’t this strategy easy to use and relatively stress-free? With practice, the chances of your students remembering and retaining times table facts are greater.

You can help laminate the strips and then get your students to keep them in their stationery cases to use in working out sums. Feel free to use a calculator to double-check the answers.

Have a go with this strategy. Your students and you can enjoy multiplying numbers accurately and in the shortest possible time.

Do you think bigger numbers in thousands can also be worked out with the multiplication strips? Try it out and see if it works!

Until next time!

 

Aishah Binte Abdullah, Albel
Lead Educational Therapist
RETA Fellow