I’m not aware of any mathematical meaning to “continental”, so I think you may mean complementary.
The complementary angle for 47° is 43° because 90-47=43. Also, because an angle represents rotation, 360° is equivalent to 0°, therefore any multiple of 360° is also equivalent to 0°. The equivalent angle to 43° between 500° and 1000° is 720+43=763°.
We can also subtract 360° to get negative angles 43-360=-317°, which is between -500° and 0°.
We can do the same for 47°: 47-360=-313°.
I hope this helps.