Autumn Shawl deisgned by Lijuan Jing plus Math?

[Sheri]

I purchased this pattern from Jojoland.com. The entrelac shawl is now completed and you add a cobweb frill by Barbara Walker (Second Treasury of Knitting). I've tried to find a way to contact Lijuan Jing and haven't found a way. My question is this:

The shawl edge has 405 stitches and the cobweb frill has 250.7 or 251 stitches.
((Originally the frill had a cast on of 376 but at one point you have to drop a certain amount of stitches, so I divided 376 by 3 which gave me 125.3 and subtracted that from 376 to give me 250.7))
I am suppose to attach the frill to two edges of the shawl by taking one stitch from the cobweb and one from the shawl and knitting the two together. My math shows me that every 1.5 stitches from the shawl is suppose to be knit together with the frill but that won't work. Does anyone have any idea how I should try and do this????? I have placed markers every 20 stitches on the shawl edges. Thanks in advance.