If you speak Korean, it's actually worse. Netflix subtitles were trying to do him a favor. His tone and verbiage was EXTREMELY sarcastic and condescending.
Closer translations would be:
"Do you know how to add and subtract (basic math)? Do you want to try to add and subtract?"
He also called Hyun-joon a coward but used a verbiage closer to "are you a pussy?"
If Hyun-gu's intention was to get himself famous outside of winning The Devil's Plan, then he's not doing himself any favors. Korea's opinion of him online is very negative.
照copy
唔識韓文 唔知真定假
不過我睇嗰時覺得佢係唔明點解咁簡單都唔做>想串人

