Lol, it's not 600 / 1.15 but 600 x 0.85 (if we account for 15% fees) because you are only keeping 85% of money. and it's 15% off every case.
So it's 0.60 x 0.85 = 0.51
and then 0.51 x 1000 = 510e
510-380 = 130
Basic math for you. I know ppl say russians are stupid but I thought it's a meme. Now I see it's reality.
or you could just do 600x0.85 which is also 510 and then just 510 - 380
idk where you took that 1.15 from