Complete 1 + __ = 5.
Incorrect answer: 5
The missing part is not the total. In 2 + __ = 5, the blank is 3, because 2 and 3 together make 5.
Giving the total instead of the missing part
The blank is one part of the total, not the whole group. Use the known part to find what is missing.
The correction
4
There are four empty spaces after placing one object in a five-frame.
- Draw five boxes in one row.
- Fill some boxes, then count the empty boxes.
- Say the two parts and the total: filled boxes plus empty boxes equals five.
Try the reasoning in another example
Complete 4 + __ = 5.
- Start at four and add one object.
- The total becomes five.
Answer: 1
Explain why each step preserves the quantity or relationship. If you can compute the answer but cannot explain the step, revisit the model before adding more questions.
The short check below reuses the first example as a retrieval question and adds a second question. It checks this method; it does not establish a grade level.
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