bearisgray

Looks like you already have your squares cut -

But if you wanted to cut all of them from one piece of fabric:

The way I figured this:

Assumptions:
(1)You are not fussy cutting? Fussy cutting is cutting so only certain parts of a pattern/stripe/design is showing - it usually takes more fabric than 'just cutting'
(2) You are cutting all the blocks from one fabric

The basic steps are:

1) How many squares can one get from a width of fabric?
(divide width of fabric by size of square - round down to the whole number)
2) How many widths of fabric will one need?
(divide total number of squares by number of squares from one width - round up to next whole number)

I can get four 9.5 inch squares out of a width of 42 inch fabric. (9.5 x 4 = 37 inches)

63 divided by 4 = 15.75 (one needs to round up to the next higher whole number)

It will take 16 widths of fabric to cut 63 squares (one left over from the last row)

16 rows x 9.5 inches = 152 inches

152 inches divided by 36 inches = 4.222 yards