numaratorul ∈ {2,3,4} si numitorul ∈ {6,7,8,9}
Le eliminam pe acele fractii care dupa simplificare au numaratorii si/sau numitorii in afara multimilor de definitie, adica:
2/6=1/3
2/8=1/4
3/6=1/2
3/9=1/3
4/6=2/3
4/8=1/2
Ne raman: 2/7, 2/9, 3/7, 3/8, 4/7, 4/9 solutii ale problemei.
