Use a Compact Column Method to Multiply Four-Digit Numbers by a One-Digit Number

In this activity, we will practise multiplying two numbers.

 

 

 

For example, there are 1,362 horses. Each horse has 4 legs. How many legs are there altogether?

 

We need to multiply to find the total number of legs.

Number of legs = 1,362 × 4

 

Let's look at how to use a compact written method to work this product out.

 

First, we multiply the ones.

4 x 2 = 8

 

Next, we multiply the tens.

4 x 6 = 24

Note that we place the 2 underneath the hundreds column, ready for step 3.

 

Now we can multiply the hundreds.

4 x 3 = 12

We add on the 2 from step two and write 14 as above, with the 1 being placed below the thousands column.

 

Lastly, we multiply the thousands.

4 x 1 = 4

We add on the 1 from step 3 and write 5 in the thousands column.

 

So there are 5,448 legs altogether.

That's a lot of legs!

 

 

Now let's try some questions.