I found the rather curious non-word “skeptable” in a posting, and wondered just how often people used this particular bastardization of the word skeptical. The answer is ::google(“skeptable”, “quite a lot”)::. Try for instance this link from Waukegan Schools that instructs parents on how to educate their children:

Have a ZERO tolerance for ANY grade below C!!!

Have a very skeptable attitude toward any grade below a B!

The more you adhere to this, the better your child will do in school.

No doubt they think it is a perfectly cromulent word.