Thread: Need help with the maths....old brain hurting!

I want to make a quilt top consisting of HSTs pieced into chevrons....so, just HST's to do...simple, clean, neat. Now, am I correct, or rather is my maths correct that the smaller the chevrons, therefore the smaller the HST's therefore the more fabric I will need as I am using more blocks or rather, seams, to maintain my quilt size? By my calculations, making my top and keeping the measurement the same, out of finished 8" chevrons consisting of 4 HST blocks of 4.5 inches each, I will use almost half as much fabric as I would if I was making the finished chevrons 6" or even 7"each? Dear oh dear am I right? Am I waaaaaay off and in need of remedial arithmetic classes?

p.s. I'm blushing just thinking about the eye rolls and guffaws of mirth coming from you all!!

This is the reason I love having Electric Quilt 7. No more math problems. I would look to Google for information:
https://www.google.com/search?q=HSTs...utf-8&oe=utf-8

I did this design for a friend who wanted to see how to make one. You need to state what size of quilt you want including borders and then that will be the size of your HST. Remember the 7/8" you need to add to the size of the finished block size. Hope this helps.

Not necessarily. It really depends on how many pieces you can get out of one strip of fabric. For example:

size of finished item: 60"x60"
size of finished HST: 4" (2 squares cut at 4 7/8" will yield 2 HSTs--round up to 5" for easier calculation)
amount of HSTs needed: 175 (60"divided by 4"=15 wide x 15 long)
amount of squares needed: 88 of each colour (one square of each colour will yield 2 HSTs)

With me so far?
If we figure that your fabric has 40" useable width, and that you are cutting 5" squares, you can get 8 squares per strip 5" strip of fabric. Because you need 88 squares, you need 11 strips of fabric (total needed divided by amount per strip). Therefore, you would need 55" of each fabric.

BUT if you made those HSTs 6" finished, you would then have to cut your squares at 7". So lets do the same math. 60"x60" divided by 6" =100 finished blocks which means you would need 50 of each colour. But you would only be able to get 5 squares out of each strip of fabric. (40 divided by 7) which means that you would need 10 strips and that would equal 70" of each colour.

It really comes down to how many squares you can cut from your useable width of fabric. Sometimes bigger is not more economical.

You and bearisgray are completely right that the more seams, the more fabric in the quilt. And Ginger is correct in pointing out that you have to consider fabric width and how you will be cutting the pieces when you calculate how much yardage to buy. However your calculation of using only half as much fabric for 8" chevrons as for 7" ones seems a bit extreme. I don't know what method you were using to calculate (whether fabric length needed, or fabric actually used in the quilt) so can't check your math. Can you show us how you came to that conclusion?