Free printable practice
Adding Whole Tens To 3 Digit Number Missing Addend Practice Activities
Grade 2 worksheets help children find the missing whole-ten addend when adding to a 3-digit number.
Practice that builds confidence
Understanding the skill
These Grade 2 addition worksheets focus on finding the missing whole-ten addend in equations such as 243 + ___ = 283 or ___ + 156 = 196. Children practise seeing that the ones digit stays the same while the tens place changes by 10, 20, 30, and other whole tens.
The printable activities include clear number sentences, missing addend problems, and space for children to work out the difference between the starting 3-digit number and the total. They build confidence with place value, mental math, and addition facts in a focused way.
In this collection, children work with 3-digit numbers and add a multiple of 10, then identify the missing addend. The unknown number is a whole ten, such as 10, 40, 70, or 90. Because only tens are being added, children learn to look closely at the tens place while checking that the ones place remains unchanged.
How the thinking progresses
A child may begin with problems like 125 + ___ = 145, where the change is easy to see. Later, they may solve equations such as 368 + ___ = 428, where the hundreds digit changes because the tens roll over. These examples help children connect addition to place value instead of relying only on counting by ones.
A simple parent routine
At home, ask your child to read the whole equation aloud: “236 plus something equals 286.” Then have them compare the first number and the total. Prompt with questions like, “What changed in the tens place?” and “Did the ones stay the same?” Children can count up by tens, use a number line, or subtract the starting number from the total to confirm the missing addend.
Classroom uses for teachers
Teachers can use these printables for independent practice, small-group reteaching, math centers, or quick checks after a lesson on adding tens. They also work well for partner talk: one student explains how the tens changed, while the other checks the equation by adding the missing whole ten back to the 3-digit number.
Common errors to watch for
Some children add to the ones place and write answers like 5 or 8 instead of 50 or 80. Others notice the hundreds digit changed but miss that the change came from adding enough tens. Encourage students to compare the full numbers, not just one digit. If regrouping is involved, show that 390 + 20 becomes 410 because ten more ones are not being added; two more tens are.
Free printable PDF download
Use this Grade 2 adding whole tens to 3 digit number missing addend worksheet page to preview the activity, print it, or download it as a PDF for quick practice. It works well for homework, homeschool lessons, tutoring, morning work, revision, and classroom centers.
Answers and answer key support
After the child completes the worksheet independently, parents and teachers can use the answer support or answer key information to check the work, review mistakes, and choose the next practice step.
Why iBloom worksheets help
These iBloom worksheets keep the practice tightly focused on one Grade 2 addition skill, so children can build fluency without distraction. A helpful child-friendly strategy is: “Compare, count tens, check.” Compare the start and end numbers, count up by tens to the total, then check by putting the missing addend back into the equation.
Helpful answers
Frequently asked questions
What does “whole-ten missing addend” mean in these worksheets?
It means the unknown addend is a multiple of 10, such as 20, 50, or 90. Children find the number that must be added to a 3-digit number to reach the given total.
What place value idea should my child use for these problems?
Your child should focus on how the tens place changes while checking the ones place. In some problems, the hundreds place may also change when the added tens cross a hundred.
Can children solve these without written subtraction?
Yes. Many Grade 2 children can count up by tens from the starting number to the total. Subtraction can be used as a check, but the main goal is understanding the missing whole-ten addend.
Why does the ones digit usually stay the same?
Because the addend is a whole ten, no ones are being added. For example, in 247 + 30 = 277, the ones digit remains 7 while the tens increase by 3 tens.
How can I help if my child writes 4 instead of 40?
Ask your child to say the amount in tens: “four tens.” Then connect that to 40 and have them check by adding 40 to the starting 3-digit number.
Is this Grade 2 adding whole tens to 3 digit number missing addend worksheet free?
Yes. You can preview it for free and use the printable worksheet for home or classroom practice.
Can I download this Grade 2 adding whole tens to 3 digit number missing addend worksheet as a PDF?
Yes. Use the worksheet download option to save a printable PDF, or print the worksheet directly from the page.
Does this Grade 2 adding whole tens to 3 digit number missing addend worksheet include answers or an answer key?
When the activity has fixed answers, iBloom includes answer support so parents and teachers can check the completed worksheet.