Confusing exam prep question

[sergols]

Can you please tell me what would be the correct answer for this question I ran across? All the answers supplied seem to be correct in practice, and I just want to get what the answer should be if anyone can help me. Thanks in advance, here is the question:

An apartment building has a calculated load of 500 amprese as determined by Article 220. Of the 500 amprese of load, there are 200 amprese of electric range and dryer load as determined in accordance with Table 220.18 and Table 220.19. The service 120/240 volt, single phase. What is the service neutral load?

 

[charlie b]

Re: Confusing exam prep question

Start by separating the 200 amps of range and dryer load from the remaining 300 amps. You only count 70% of that 200 amps, or 140 amps, per 220.22. That gives you 140 plus the remaining 300, for a total (at this point) of 440.

Of this value, you count 100% of the first 200 amps, and 70% of the remainder, again per 220.22. So add 200 plus 70% of 240. My answer is therefore 368 amps.