a row of five 12" blocks = 60"
a row of ten 6" blocks = 60"
a row of fifteen 4" blocks = 60"
or
make a 12" block, beside that sew three 4" blocks, then an 8" with two 4" blocks underneath, results in 24" X 12" table runner - or two sets makes 24" square.
here is what I mean
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