Ndinabantwana ababini nonyana owazalwa ngolwesine. Ngawaphi amathuba okuba ndibe nentombi? Masichaze iintsuku zeveki ngamanani \(1, 2, … , 7\) ngo \(1\ =\) ngoMvulo, \(2 =\) NgoLwesibini njalo njalo. Ngoku sinokusichaza isiganeko ngokuthi "ngomhla \(n\) wokuzalwa kwenkwenkwe" njenge \(B_n\) , kwaye ngokufanayo \(G_n\) .
Umzekelo, \(B_3\) uthetha inkwenkwe ezelwe ngoLwesithathu kwaye \(G_1\) ithetha ukuba intombazana izalwe ngoMvulo. Sisebenzisa olu bhalo singabhala iziganeko ezinje: \(B_3G_1\) ithetha: "Owokuqala umntwana yinkwenkwe ezelwe ngoLwesithathu aze owesibini abe yintombazana ezelwe ngoMvulo".
Makhe sicinge ukuba amathuba okuba umntwana azalwe yonke imihla yeveki alinganayo (okuthi, njengesini somntwana, asiyonyani ngokupheleleyo, kodwa yingcinga efanelekileyo yokugcina ingxaki ilula). Oku kukhokelela koku kulandelayo \(27\) ngokulinganayo iindlela abantwana bam abanokuba bazalwe ngayo ( \(B_4\) imele inkwenkwe ezelwe ngoLwesine):
$$
\begin{matrix}
B_4G_1 & G_1B_4 & B_1B_4 & B_4B_1\\
B_4G_2 & G_2B_4 & B_2B_4 & B_4B_2\\
B_4G_3 & G_3B_4 & B_3B_4 & B_4B_3\\
B_4G_4 & G_4B_4 & B_4B_4 & \\
B_4G_5 & G_5B_4 & B_5B_4 & B_4B_5\\
B_4G_6 & G_4B_4 & B_6B_4 & B_4B_6\\
B_4G_7 & G_7B_4 & B_7B_4 & B_4B_7
\end{matrix}
$$
Itheyibhile engentla luluhlu olupheleleyo lwazo zonke iindlela abantwana ababini abanokuzalwa ngayo ukuba omnye wabo yinkwenkwe ezelwe ngoLwesine. Ewe, phantsi kweengcinga zethu, zonke ezi ziganeko zinokwenzeka ngokulinganayo. Kukho \(27\) okunokwenzeka apho \(14\) (ezo zikwiikholamu ezimbini zokuqala) zinentombazana. Ngoko ke amathuba okuba ndibe nentombi \(14/27\approx 51,9\% \neq 50\%\) .