Answer:
3.12 meters
Explanation:
You already know that the answer is 9.36/3. Since all of the digits in the dividend are divisible by 3, you can easily do this division in your head (mental arithmetic). The first attachment shows it done using the usual long-division format.
The second attachment shows a calculator result--which is what most of us might use if we don't want to do the mental arithmetic.
We're never quite sure what "show your calculation" is supposed to mean when the result is computed without writing anything down.
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Each section is 3.12 meters long.