삼십
samsip · TOPIK 1
thirty
삼십 = 삼 (three) + 십 (ten): three tens make thirty
Sino-Korean numbers stack like multiplication: 삼 (三, three) placed before 십 (十, ten) means three tens. The same pattern gives 이십 (twenty) and 사십 (forty), so knowing 1-10 unlocks every multiple of ten.