Ignoring the multiple ambiguities as pointed out by JBD, and taking the wording at face value, I'd say that the 80 kva per phase is simply 80 kva, 3-phase. Just like 50 amps per phase is simply 50 amps, 3-phase.
Therefore, the amperages would appear to be
80,000/(240x1.73) = 192 amps
Then, taking the single phase numbers at face value, I'd assume L-N connections because the problem specifies individual phases. This means that phase A would have an additional 283 amps, and phase C, an additional 341 amps.
So...
Phase A = 192 + 283 = 475 amps
Phase B = 192 amps
Phase C = 192 + 343 = 535 amps
Then again, according to some hard-to-follow explanation to a similar sounding problem in "Delmar's Standard Textbook of Electricity" these numbers are probably wrong.
[This message has been edited by Redsy (edited 02-10-2006).]
