He aha te mati teitei ka taea e tētahi tau matua te mutu? I runga i te pātai o mua, tuhia he horopaki kei roto te whakautu. Ka taea te 1 - 20 rerenga kōrero. Te horopaki:
Nō reira, ehara te 6 i te tau matua. Ko te pikitia i te taha matau e whakaatu ana ehara te 12 i te tuatahi: 12 = 3 · 4. Kāore he tau tau nui ake i te 2 he matua nā te mea i runga i te whakamāramatanga, he iti iho i te toru ngā kaiwehe motuhake, arā, 1, 2, me te n. E tohu ana tēnei kāore a n i te tuatahi. Na reira, ko te kupu tuatahi takitahi e pa ana ki tetahi tau matua nui atu i te 2. Waihoki, ina tuhia ki te pūnaha ira noa, ko ngā tau matua katoa nui ake i te 5 ka mutu ki te 1, 3, 7, 9, i te mea ko ngā tau tauwehe he tini o te 2 me ngā tau e mutu ana ki te 0 me te 5 he tini o te 5.