Practice

Think About It!

Goal: Do you remember how to write a subtraction sentence?

We can find the remaining number of aliens by writing a subtraction sentence. Remember, subtraction is when we take numbers away. If there were 13 aliens sitting on moon rocks, and 6 of the aliens had to go home for dinner, our subtraction sentence would look something like this:

13 is the first number in this subtraction sentence. It represents the total number of aliens sitting on moon rocks. 6 is the second number in this subtraction sentence. It represents the number of aliens who had to go home for dinner. That means that 13 is the whole, and 6 is one of the parts. When we subtract these numbers, we will find the remaining part.

Whole - Part = Part

Great job subtracting! You were able to find the difference, or the missing part, by counting the number of aliens that remain on the moon rocks. You have already worked very hard learning about subtraction sentences and strategies. Today, you will not only be finding the difference in subtraction sentences, but also finding pictures that represent subtraction sentences. Let’s try!

11 - 3 = ____

Here is the subtraction sentence 11 - 3. Let’s watch how a picture can be used to represent this subtraction problem. Before we begin, ask yourself: What do I already know? Do you know the whole? Do you know the part?

Click on the whole in the number sentence below. Click on the part in the number sentence below.

Whole: Total number of objects

Part: Number of objects crossed out

Let’s look at a picture that represents 11 - 3. Click the picture below!

Question

This picture represents a subtraction sentence. What is the whole of the subtraction sentence?

Answer

7 is the whole because there are a total of 7 astronauts.