Numbers 4:35 WEB

³³  This is the service of the families of the sons of Merari, according to all their service, in the Tent of Meeting, under the hand of Ithamar the son of Aaron the priest.'

³⁴  Moses and Aaron and the princes of the congregation numbered the sons of the Kohathites by their families, and by their fathers' houses,

³⁵  from thirty years old and upward even to fifty years old, everyone who entered into the service, for work in the Tent of Meeting.

³⁶  Those who were numbered of them by their families were two thousand seven hundred fifty.

³⁷  These are those who were numbered of the families of the Kohathites, all who served in the Tent of Meeting, whom Moses and Aaron numbered according to the commandment of Yahweh by Moses.