Find How Many Were Added
Write start + unknown = finish.
About 15 minutes, plus any extended practice
Supplied materials
- Paper and a pencil; drawing and spoken explanations are welcome. An adult may read directions and options aloud.
- Supplied worked-case record: A tray starts with 6 counters and ends with 14.
- All quantities and shape descriptions are supplied in the worked example and questions; no purchase or personal information is needed.
Learn the idea
A change story can give the start and finish while leaving the added amount unknown. Draw the starting part inside the final whole. The uncovered part is the change. Addition and subtraction describe the same relationship from different directions.
Write start + unknown = finish. Find the gap by counting on or subtracting the start from the finish. Substitute your answer into the addition sentence to make sure it reaches the stated finish.
Label the start and finish before choosing an operation. The final total is not the number added. Draw one bar for the final total and split off the starting part.
- Draw one bar for the final total and split off the starting part.
- Follow the worked example. Point to each number or shape feature and say what it tells you.
- Write start + unknown = finish.
- Try the question and then the three practice questions. Check your answers and explain any change you make.
See the method in action
A tray starts with 6 counters and ends with 14. The unknown change is 14−6=8. Counting on eight from six reaches fourteen. Check 6+8=14; this confirms the change without confusing it with the final total. Label the start and finish before choosing an operation. The final total is not the number added. Draw one bar for the final total and split off the starting part.
Check your reasoning
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Helpful tips
- Label the start and finish before choosing an operation.
- The final total is not the number added.
See the answer and explanation
8
Find the difference between finish and start. The result is 8.
Take it further
A shelf starts with 7 cards and ends with 18. Expected: 11 added.
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More practice: try new cases
Choose an answer for each problem. Explain your method on paper, then use the feedback to decide what to revisit.
Your choices are temporary. Feedback appears after you check all the answers.
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Check the subject sources
These LifeStarter passages, scenarios and exercises are authored for this Academy with AI assistance and review. External resources keep their publishers’ terms. A grade label suggests a starting level; it does not establish alignment with your school’s complete requirements.