Adding whole tens (missing number)
Browse 0 free printable Adding whole tens (missing number) worksheets for Third Math. These Addition worksheets are designed to give students targeted practice and build confidence in math.
Worksheets are available at multiple difficulty levels — Easy, Medium, and Hard — so you can meet every student where they are. Each worksheet is an instant PDF download: print as many copies as you need for your classroom, tutoring sessions, or home practice at no cost.
Whether you're a teacher looking for addition practice problems, a homeschool parent building a Third curriculum, or a tutor helping a student catch up, these free printable worksheets are ready to use today.
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Prerequisites
Practice Questions
- ? + 80 = 110
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30
- ? + 50 = 90
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40
- ? + 70 = 100
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30
- ? + 20 = 70
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50
- ? + 60 = 90
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30
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Teacher Resources
Teaching Notes
This collection helps students practice finding missing addends when working with whole tens. Encourage them to use place value understanding by relating problems like 30 + ? = 80 to 3 + ? = 8. Use base-ten blocks or ten-frames to visualize the addition of tens.
Vocabulary
Common Mistakes
- Not recognizing tens as units (e.g., treating 30 as 3 ones instead of 3 tens)
- Basic addition errors when finding the related single-digit sum
- Confusion with inverse operations (subtraction) to find the missing addend
Differentiation
Discussion Questions
- How is adding tens similar to adding ones?
- What strategy did you use to find the missing number?
- Can you use subtraction to help find the missing addend? How?
Extension Activities
- Use fact families to solve.
- Draw pictures to represent problems.
- Play 'guess the number'.
Parent Tip
Use objects to show a total and ask how many are missing to reach it.
Learning Path
Skill Cluster
Number Sense & Place Value
Estimated Time
15 minutes