Researchers who encounter two different years of birth for a relative in records that only provide an age may wonder which is “correct.” The reality is that neither may be right. Both ages could be off and the actual year of birth could be in between the two that are suggested by the available records. Don’t just “average” them and call it a day.
Include each year of birth in your records as an alternate date and cite the source from which it was taken. There may be no other sources for the date of birth and it may be impossible to tell which of the two records is most likely to be accurate. Of course one should look for other records as much as possible, but sometimes the only sources for someone’s date of birth may be a few census records of questionable accuracy.