Hmm... I'm not quite sure how you all arrived at 4 babies born on that one day. The total was 89 babies. There are 30 days in June. If you have 4 babies born one day, then you could say there were 3 born the other 29 days.
3 babies x 29 days = 87 + the 4 babies = 91 = too many babies.
2 born on other 29 days = 58 babies + 31 babies (what I put) = 89 babies for the month of June.
And you can't have 2.93 babies born each day. So that rules out doing 89 - 4 babies = 85 babies/29 days = 2.93.
I could have interpreted the question completely wrong, but I'm not really sure...
What stinks is not being able to find out
EDIT: Oh wait, I guess you could have some days with 2 babies born... bummer.