Nginama-apula amathathu, uJack unamapheya amane futhi uJill unezincwadi ezinhlanu. Ngemva kokuba sengidle amapheya amabili kaJack, manje sesinezithelo ezingaki?
Ama-apula namapheya kuyizithelo, kuyilapho izincwadi zingeyona izithelo. Ngakho ngaphambi kokuba ngidle amapheya amabili, sinezithelo ezi-3+4=7 sezizonke. Ngemva kokudla amapheya amabili, sinamapheya angu-7-2 = 5 esewonke.