learn the korean numbers

Here are the Sino Korean numbers 1-10 with their romanizations.

1: 일 (il)
2: 이 (i)
3: 삼 (sam)
4: 사 (sa)
5: 오 (o)
6: 륙 (ryuk) or 육 (yuk)
7: 칠 (chil)
8: 팔 (pal)
9: 구 (gu)
10: 십 (sip)

then we have 10, 100, 1000, and 10,000

100: 백 (baek)
1000: 천 (cheon)
10,000: 만 (man)

when writing a number from 11-99, all you have to do is combine the korean numbers like this:

이 (2) + 십 (10) = 이십 (20) 사 (4) + 십 (10) + 오 (5) = 사십오 (45) 십 (10) + 칠 (7) = 십칠 (17) 칠 (7) + 천 (1000) + 팔 (8) + 백 (100) + 이 (2) + 십 (10) + 삼 (3) = 칠천팔백이십삼 (7,823) note that for 10,000, 1,000, 100, and 10, you do not have to say... one (일) + thousand (천), 일백, or 일십.

Here are the Native Korean numbers.

1: 하나 (ha-na)
2: 둘 (dul)
3: 셋 (set)
4: 넷 (net)
5: 다섯 (da-seot)
6: 여섯 (yeo-seot)
7: 일곱 (il-gop)
8: 여덟 (yeo-deol)
9: 아홉 (a-hop)
10: 열 (yeol)
From 11 to 19 you just put the number 10 and add another number after it.
20: 스물 (seu-mul)
30: 서른 (seo-reun)
40: 마흔 (ma-heun)
50: 쉰 (swin)
60: 예순 (ye-sun)
70: 일흔 (il-heun)
80: 여든 (yeo-deun)
90: 아흔 (a-heun)
The same rule as previously mentioned for 11 through 19 applies to 21-29, 31-39, 41-49, and so on. for bigger units like 100, 1,000, 10,000 and so on, the words for these bigger units in the native Korean numbers are no longer used, and only sino-Korean numbers are now used.
When you want to say 101, 102, and so on, you need to combine the systems together.
101 = 백 (baek - 100 in sino-Korean) + 하나 (hana - 1 in native Korean)

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