A student is 1.7m tall and has a mass of 60Kg. If the dimension of this student shrank by a factor of three(to1/3 previous values) estimate the mass of the shrunk student.

I think the answer is not 20 and I don't think it is that easy.
Please help me answer this question. Thank you a lot!!

Please clarify: By "dimension" do you mean simply the height?

Yes I believe it is the height.

Yes, 20kg would be the best "guestimate" but of course the subject could "shrink" in height but get fatter.