diameter of a cylinder using volume and depth

[donjlegacy]

I have been struggling with this question for a few days now and I cannot come to an answer.

(Q) If a cylindrical tank holds 1600m3 of water and has a depth of 12.0m what is its diameter in metres? Round your answer to correct number of significant digits.

In all of my attempts my answer hasn't even been close, so I think I am misunderstanding something.

One more question I have, if a question asks me to round it to the nearest whole meter, would I still round it "to the correct number of significant digits" as well?

Thanks in advance,
Don

 

[Denis]

If a cylindrical tank holds 1600m3 of water and has a depth of 12.0m what is its diameter in metres? Round your answer to correct number of significant digits.

Formula for volume of cylinder is pi(r^2)(h) ; r is the radius, h is the depth
So pi(r^2)(12) = 1600
Can you not solve that for r? The diameter will be twice that.

As far as "Round your answer to correct number of significant digits",
nobody knows I guess, since the number is not given.