Could the number of eggs or young ones produced by an oviparous and viviparous mother be equal? Why?

The numbers of eggs produced by an oviparous mother will always be more than the young ones produced by a viviparous mother. This is because in oviparous animals, the development of young ones takes place outside the mother's body. Thus, their eggs are vulnerable because of the harsh environmental conditions and predators. Therefore, to overcome the loss, more eggs are produced by mothers so that even under harsh environmental conditions, some eggs are able to survive and produce young ones.
On the other hand, in viviparous organisms, the development of young ones takes place inside the body of the mother. Since the development takes place inside the body the young one is less exposed to environmental conditions and predators. Therefore, there are more chances of their survival and hence, less number of young ones is produced compared to the number of eggs.