Subtracting two-digit numbers

You might see calculations in different ways.

Here we have a calculation, a part-whole model and a bar model.

Example 1

Let's work out the calculation

36 - 11 =

Using a place value chart to work out the answer to this calculation we start with the whole number, 36 and split it into tens and ones.

Each packet of pencils represents one ten and each marble represents one in the ones column.

36 has 3 tens and 6 ones. So we add 3 packets of pencils to the tens column and 6 marbles to the ones column.

Now we take away the second number, the part.

We always start with the ones first.

11 is made up of 1 ten and 1 one so we take off one marble from the ones column and 1 packet of pencils from the tens column.

The amount remaining is the answer.

There are 2 tens left which is 20 and 5 ones which is 5.

36 - 11 = 25

Let's take a look at this part-whole model and work out what the missing part is.

We can write this as:

56 - 42 =

As with the other example we will use a place value chart to work out the answer.

The whole number is 56 and the part 42.

Here we have 5 sets of pencils and 6 marbles representing 56.

We've taken away 4 tens and 2 ones.

What do we have left?

1 ten and 4 ones.

That means

56 - 42 = 14

Lets do another calculation, this time using a bar model.

This is the same as

88 - 32 =

Which number do you think needs to be represented on the place value chart?

88 is the whole number so we represent 88 on the place value chart with 8 tens and 8 ones.

How many ones will we take away?

How many tens should we take away?

There are 5 tens and 6 ones left which means

88 - 32 = 56

Have a go at the questions in this quiz and see if you can get them all correct.

Try and solve the calculations in this quiz.