Storage Size Math Problem!

CTOAGN

Honorable
Dec 4, 2013
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10,710
I am seeing how much a Tianhe-2 Node costs to build and I am stuck on storage. I don't know how to calculate it correctly. Here we go:

Tianhe-2 has 16000 nodes to make up one supercomputer. The computer has a combined storage space of 12.4 PB (petabytes). If the chassis I am using in my list has 4 3.5" internal hard drive slots, what is the size of each hard drive?