Numbers 1:3

3 You and Aaron are to count according to their divisions all the men in Israel who are twenty years old or more and able to serve in the army.

Read Numbers 1:3 Using Other Translations

From twenty years old and upward, all that are able to go forth to war in Israel: thou and Aaron shall number them by their armies.
From twenty years old and upward, all in Israel who are able to go to war, you and Aaron shall list them, company by company.
twenty years old or older who are able to go to war. You and Aaron must register the troops,