Korean numerals

The Korean language has two regularly used sets of numerals, a native Korean system and Sino-Korean system.

For both native and Sino- Korean numerals, the teens (11 through 19) are represented by a combination of tens and the ones places. For instance, 15 would be sib-o (십오; 十五), but not usually il-sib-o in the Sino-Korean system, and yeol-daseot (열다섯) in native Korean. Twenty through ninety are likewise represented in this place-holding manner in the Sino-Korean system, while Native Korean has its own unique set of words, as can be seen in the chart below. The grouping of large numbers in Korean follow the Chinese tradition of myriads (10000) rather than thousands (1000). The Sino-Korean system is nearly entirely based on the Chinese numerals.

The distinction between the two numeral systems is very important. Everything that can be counted will use one of the two systems, but seldom both. Sino-Korean words are sometimes used to mark ordinal usage: yeol beon (열 번) means "ten times" while sip beon (십번; 十番) means "number ten."

When denoting the age of a person, one will usually use sal (살) for the native Korean numerals, and se (세; 歲) for Sino-Korean. For example, seumul-daseot sal (스물다섯 살) and i-sib-o se (이십오 세; 二十五 歲) both mean 'twenty-five-year-old'. See also East Asian age reckoning.

The Sino-Korean numerals are used to denote the minute of time. For example, sam-sib-o bun (삼십오 분; 三十五 分) means "__:35" or "thirty-five minutes." The native Korean numerals are used for the hours in the 12-hour system and for the hours 0:00 to 12:00 in the 24-hour system. The hours 13:00 to 24:00 in the 24-hour system are denoted using both the native Korean numerals and the Sino-Korean numerals. For example, se si (세 시) means '03:00' or '3:00 a.m./p.m.' and sip-chil si (십칠 시; 十七 時) or yeol-ilgop si (열일곱 시) means '17:00'.

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