The committee members were relieved to find that their conclusions coincided.

coincided 是动词 coincide 的过去式。coincide 由前缀 co-（表示"共同"）和词根 -incide（来自拉丁语 incidere，意为"落下"）组成，字面意思是"同时落下"，引申为"同时发生""一致""相符"的意思。在这里表示"结论相吻合、达成一致"。