Adding and Subtracting 10- Word Problem Practice
Why Adding and Subtracting 10 Gets Tricky in Word Problems
Kids who can solve 8 + 10 = 18 in a heartbeat often freeze when that same problem shows up inside a sentence. The number sentence is isolated. The word problem requires kids to first understand what's happening, then translate it into math.
That's the disconnect. Most children haven't been taught to pull apart word problems systematically. They read the story, panic, and guess.
This guide fixes that.
The Four Problem Types Your Child Needs to Know
Every word problem about adding or subtracting 10 falls into one of four categories. Teach these explicitly. Kids who know the structure solve problems; kids who don't guess.
1. Join Problems (Something Gets Added)
Two groups combine. One group exists, then more join it.
Example: Maya had 34 stickers. She got 10 more for her birthday. How many does she have now?
These are the easiest for kids to grasp because "got" and "found" signal addition.
2. Separate Problems (Something Gets Taken Away)
One group loses members. The action goes backward.
Example: There were 52 birds on the wire. 10 flew away. How many are left?
Watch for words like lost, gave away, ate, and flew away. These all mean subtraction.
3. Compare Problems (What's the Difference?)
Two groups exist. The question asks how much bigger or smaller one is.
Example: Jake has 67 baseball cards. Tyler has 10 fewer. How many does Tyler have?
These confuse kids because there's no action happening. Someone just has less. The key word is fewer or more.
4. Part-Part-Whole Problems (What's the Total or Missing Part?)
Two parts make up a whole. The question asks for one of them.
Example: A pet store has 45 dogs and 10 cats. How many pets are there in total?
These require kids to see that both parts belong to one group.
How to Solve Any Word Problem: A Step-by-Step Method
Don't let kids just "read it and figure it out." That's not a strategy. Here's what actually works:
Step 1: Read the Whole Problem Once
Just read. Don't solve anything. Get the general idea of what's happening.
Step 2: Identify the Action
Ask: Is something joining, leaving, or are we comparing? Circle the action word that tells you what type of problem this is.
Step 3: Find the Numbers
Underline the starting number. Circle the 10 if it's there. Box the question word (how many, what's left, total).
Step 4: Write a Number Sentence
Translate the story into math before solving. If 10 joined, write +. If 10 left, write −.
Step 5: Solve and Check
Use mental math or a number line. Then ask: Does this answer make sense?
Quick Reference: Words That Signal +10 vs. −10
| Adding 10 | Subtracting 10 |
|---|---|
| got, received, found | lost, gave away, sold |
| bought, earned, collected | ate, used, broke |
| joined, added, brought | flew away, left, went away |
| more, extra, in total | fewer, less, remaining |
Common Mistakes Kids Make
- Guessing the operation from the numbers. They see 10 and assume it goes in the problem somewhere. They don't analyze the story.
- Ignoring the context. A problem about sharing cookies doesn't care about adding 10 just because 10 appears in the sentence.
- Forgetting to add the 10. They solve the base number and forget the 10 entirely. "45 + 10 = 45." Yes, this happens.
- Reading too fast. They see "10 more" and compute "45 − 10" because they didn't catch the word more.
Getting Started: Practice Problems
Work through these with your child. Read each problem aloud. Identify the type. Then solve.
Problem 1: Sami had 28 crayons. She got 10 more for her birthday. How many crayons does she have now?
Type: Join. | Number sentence: 28 + 10 = ? | Answer: 38
Problem 2: There were 73 cars in the parking lot. 10 cars drove away. How many cars are still there?
Type: Separate. | Number sentence: 73 − 10 = ? | Answer: 63
Problem 3: Emma read 56 pages. Lucas read 10 fewer pages than Emma. How many pages did Lucas read?
Type: Compare. | Number sentence: 56 − 10 = ? | Answer: 46
Problem 4: A farmer has 39 chickens and 10 ducks. How many birds does the farmer have altogether?
Type: Part-Part-Whole. | Number sentence: 39 + 10 = ? | Answer: 49
When to Move On
Your child is ready for harder problems when they can:
- Correctly identify the problem type in 3 seconds
- Write the number sentence before solving
- Explain why they chose to add or subtract
Until then, stay on this level. Rushing ahead just builds confusion that you'll spend months untangling later.
These problems aren't complicated. The skill is reading comprehension applied to math. Once kids get that structure, adding and subtracting 10 word problems stop being mysterious and start being straightforward.