Where is the number lock on the A1048?

Try the key right above the number 7. (the "CLEAR" button above the number pad ) Also see if you can set a specific key in System Preferences Keyboard:Shortcuts... or in whatever emulator or software you're using. (The Apple numeric keypad is meant for entering numeric data only, and is rarely if ever used as a substitute for the arrow keys. They don't even have arrows drawn on the numeric keypad. Num lock is a distinctly WinDUHows thing. - Mac's have never used it).

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