A missing part can be written two ways. Both mean the same thing.
Step 1: Let's Learn
Read it, or press Listen and follow the words.
Two sentences, one idea
4 + ? = 7 and 7 − 4 = ? both ask the same question.
4 and 3 makes 7.
Part you have
Whole
Two ways to ask the same question
The sentence 4 + ? = 7 asks what to add to 4 to reach 7. The sentence 7 − 4 = ? asks what is left when 4 is taken from 7. They look different and they have the same answer, because they describe the same three numbers.
Find the whole first
In every one of these sentences, one number is the whole and the other two are its parts. The whole is always the biggest. Once you have spotted which number it is, you know whether to add the parts together or take one part away.
Step 2: Try It Yourself
Tap and try it out.
3 and 5 makes 8.
Step 3: Watch an Example
One step at a time.
Watch Ana Find the Missing Part
Ana has 4 stickers. She wants 7.
- Step 1
She thinks: 4 and how many more make 7?
Step 4: Your Turn
Practice makes it stick.
Collecting Shells
Problem 1 of 1
Ben has 5 shells. He wants 9. How many more does he need?
How Many More?
Count up from the part you have.
1 of 2
6 + ? = 9
2 of 2
2 + ? = 8
Step 5: Quick Check
Show what you know.
Question 1 of 2
3 + ? = 7
Question 2 of 2
5 + ? = 10
What You Learned
- A missing part is a kind of subtraction.
- 4 + ? = 7 asks the same thing as 7 − 4.
- Count up from the part you already have.