～割
～わり · ～wari · JLPT N1 · noun
percentage
💯 割 = divide: 割 means cutting into parts, and ～割 cuts a whole into tenths, so 3割 is 30 out of 100.
割 (wari) means a tenth part, from the idea of cutting something into pieces. 十割 is the whole 100%, so 3割 means 30%.
割 — 害 (harm, phonetic) + 刂 (knife radical)
A semantic-phonetic compound: the knife radical 刂 gives the meaning 'cut,' while 害 supplies the sound. The original sense was to cut or slice with a blade, which extended to 'divide' and 'allot a share.' Modern uses like 割爱 (give up something dear) preserve this idea of cutting away.