Be sure you add the 4" on the top, bottom and each side when you use the length and width of the back -- otherwise you don't have enough backing if you are going to have it longarmed.
I did it by hand and got the same answer of 101" (actually 100.827...) that the calculator came up with -- Yeah!! I can still do algebra.
Last edited by QuiltnLady1; 06-02-2012 at 04:07 PM.