Platinum is a very rare metal, even rarer than gold. Its density is $21.5g/cm^3$. Assuming that the world production has been about $110$ tonnes for each of the past $50$ years, and negligible before that, which of the following has a comparable volume to that of the total amount of platinum ever produced?
A: a shoe box, B: a cupboard, C: a house, D: Buckingham Palace, E: the grand Canyon
If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.
This problem is taken from the UKMT Mathematical Challenges.