Find an unknown addend
In today's lesson, we will be finding an unknown addend when the sum is changed.
Video
Click on the play button to start the video. If your teacher asks you to pause the video and look at the worksheet you should:
- Click "Close Video"
- Click "Next" to view the activity
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Lesson summary: Find an unknown addend
The next lesson in Extending calculation strategies and additive reasoning is "Introduction to same difference"