No, it is not possible that number of eggs or young ones produced by an oviparous and viviparous mother are equal because the number of eggs produced by oviparous mothers is more because in oviparous animals, fertilization talks place outside the body whereas in viviparous animals’ development takes place inside the body which makes successful incubation of young animals .

When eggs are present outside, there is a risk of getting eaten by predators due to their immobility present in eggs. Thats why in order to sustain the progeny, there is a requirement for more of eggs.