Sometimes a part is missing. The box shows where it hides.
Step 1: Let's Learn
Read it, or press Listen and follow the words.
Count on to find it
For 6 + ? = 9, start at 6 and count up to 9. That is 3 hops.
6 and 3 makes 9.
Known part
Whole
The box is a number you have not found yet
It is not a mystery or a trick. It is a real number that already has a value — your job is to work out which one.
Always put it back
Found 4 for 3 + ? = 7? Put 4 in and read it: 3 + 4 = 7. If it reads true, you are right, and you did not need anyone to tell you.
Step 2: Try It Yourself
The dashed box is the missing part.
4 and 5 makes 9.
Step 3: Watch an Example
One step at a time.
Watch Mia Find the Box
Mia sees 7 + ? = 10.
- Step 1
She starts at the part she knows: 7.
Step 4: Your Turn
Practice makes it stick.
The Bookshelf
Problem 1 of 1
Leo needs 8 books. He has 5 already. How many more does he need?
Fill the Box
Count on from the part you know.
1 of 3
4 + ? = 7
2 of 3
6 + ? = 10
3 of 3
2 + ? = 9
Step 5: Quick Check
Show what you know.
Question 1 of 2
5 + ? = 9
Question 2 of 2
3 + ? = 10
What You Learned
- A missing part can hide anywhere in a sentence.
- Start at the part you know.
- Count up to the whole and count your hops.