# Addition and Subtraction Within 100

*Time: 15 min. 6 questions.*

## Instructions

Answer each question in your notebook. You can draw pictures, use a number line, or use counters to help you. Try your best on every question!

## Questions

1. Maria says: "10 + 20 + 30 is the same as 30 + 10 + 20." Is she correct?

A) True
B) False ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29844))

2. Fill in the missing number: 45 + ___ = 45 + 20 ([Details](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846))

3. What is 100 made of? Circle the correct answer.

A) 5 tens
B) 10 tens
C) 20 tens
D) 100 ones and nothing else ([Details](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846))

4. Show two different ways to make the sum 17. Use addition facts with addends to 10. ([Details](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846))

5. Tom has 62 stickers. He gives away some stickers and now has 45 stickers. How many stickers did Tom give away? ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29844))

6. A student adds 38 + 25 and gets 63. How can they check if this answer is correct, using subtraction? ([Details](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846))

## Curriculum coverage

| Question | Outcome alias |
|---|---|
| 1 | [Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29844) |
| 2 | [Details](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846) |
| 3 | [Details](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846) |
| 4 | [Details](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846) |
| 5 | [Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29844) |
| 6 | [Details](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846) |

## Answer key

1. **True.** Addition order does not change the sum, so adding numbers in any order gives the same total ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29844)).

2. **20.** Both sides start with 45, so the missing number must match 20 to make the equation balanced ([Details](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846)).

3. **B) 10 tens.** The number 100 can be shown as ten groups of ten ([Details](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846)).

4. **Sample answer: 10 + 7 = 17 and 9 + 8 = 17.** A sum can be made in more than one way using different addition facts ([Details](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846)).

5. **17 stickers.** Subtracting 45 from 62 gives the number of stickers Tom gave away, since 62 − 45 = 17 ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29844)).

6. **Subtract 25 from 63.** If 38 + 25 = 63 is correct, then 63 − 25 should equal 38, which checks the addition using the inverse operation ([Details](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846)).

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*AILI quiz · language en · model claude-sonnet-5 · generated 2026-09-17 · id bfb7c23f-123c-440f-8a30-236364426252*

### Sources

- node:n1: Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29820)
- node:n2: How can addition and subtraction be interpreted? (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29843)
- node:n3: Students investigate addition and subtraction within 100. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29844)
- node:n4: Details (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846)