夥 is the traditional/literary form of 伙. In modern simplified Chinese, 伙 is standard. You'll mainly encounter 夥 in classical texts, legal documents, or traditional Chinese writing.
history
Originally meant 'a large group' or 'many.' The meaning of 'companion/partner' developed from people gathering in groups to share meals (火 = fire for cooking).
果 (guǒ) supplies the sound, drifted to huǒ. There's a quiet semantic echo too - a tree heavy with fruit is the very image of plentifulness, which is exactly what 夥 means (a lot, a crowd, a partner-band). Same phonetic: 裹, 颗, 课.
多 (many) reinforces the meaning directly: 夥 is a partner in plurality. The character functions both as the traditional form of 伙 (partner / band) and as a literary intensifier - 夥矣 (how many!). 多 stacks two 夕 (evenings), which is also why 夥 indexes under Kangxi #36 夕 (xī).
Filed under radical 夕 (xī, #36) by convention. 夕 is not a separate component in 夥, so no strokes are highlighted.
