Jeanette- thanks so much for your input!
I must have measured wrong because when I sewed it all up it was app. 100X115.
I put it on the bed and it was perfect! Nice and long and nice and wide. My mattress isn't one of those really big ones. I guess you would call it standard. I believe it has a pillowtop but not too thick.
I'm sending it out this weekend.
Thanks, all!