Also take into account your yeast!!! The alcohol tolerance for each strain of yeast will determine the amount of residual sugars--> how sweet or dry will your mead finish. The additional fermentable sugars (from fruit, juices, etc) will add to the overall picture.
Just honey and water will have a PABV of 14.85% --> most yeasts will ferment to dryness.
Honey + fruit + water will raise the PABV ( say 16.11%) ---> many yeasts will leave residual sugars after fermenting to completion.
Hope that helps,
Ted