Hello! Let me know if you find any errors in my solution.
The volume of a cylinder = πr2h
We know:
v=780cm3
h=12cm
Now we plug in those values:
780cm3=πr212
And isolate the variable r:
780cm312cm=πr265cm2π=r2r=√65cmπ
And round the radius to the nearest tenth:
r=√65πr≈8.1ππ≈3.1r≈8.13.1≈2.6cm
Therefore, the answer is 2.6cm
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