The formula for each piece is this: Subtract 1/2" from each dimension. Divide each dimension by 2. Add 1/2" to each dimension.

Example: 8 1/2" x 4 1/2" rectangle to be made half size.

8 1/2" - 1/2" = 8. Divide by 2 = 4. Add the 1/2" back = 4 1/2"

4 1/2" - 1/2" = 4. Divide by 2 = 2. Add the 1/2" back = 2 1/2".

Solution??? Try another pattern!!! T his is getting FAR too technical for me!!!!!!!!!!!!!!!!!!! :roll:

Oh I totally agree! me and algebra got along great most days, but basic math, not so much! I wanted to make a miller's crossing quilt, but I wanted 12 inch blocks, not 6 inch blocks, so instead of googling it to find the correct measurements, I just double everything. NOPE!! All my 9P on point pieces don't have points, and my pinwheel blocks have little borders on them. Good luck though, you may get it!

the 1/4" seam allowance also applies to each unit within the block.

A finished 12" block which is not joined to other blocks is 12 1/2".

Reduce finished 12" (not 12 1/2) to 6". But you have to add 1/4" to each component of the block and the outside seams.

A triangle in a sqare would be plus 1/2" for the outside seams, no extra width-wise, but plus 3/8" plus 3/8" for both sides of the triangle height-wise. (triangle is pointing up or down)

A pinwheel would be plus 1/2" outer SA plus 1/2" inner SA both directions, ditto a sq in a sq.

i would have to agree with the subtract seam allowance divide by 2 then add seam allowance back .

really depends on the block and how many pieces!

I am not even jumping in this mud puddle.

Love graph paper. The word you are looking for is 'educational'.

I HATE MATH....lol

I would love to see the actual pattern you are trying to change.
Not going there with measurements!