Designing The Split Herringbone Quilt: Part 4 Fabric Math

 After deciding how many of each block I wanted next came time to work out how much background fabric I would need.

On the blocks I'd already drawn I used symbols to represent the different widths.

For example on the A block to the left you might just be able to see an asterisk, triangle and diamond. 

The asterisk represented the background triangles, the diamond's are the colour strips that measure 3/4'' wide and the triangles are the background strips that measure 3/8.

On the bottom of the picture I have written it out so I know in each A block I need:

▲= 3 
♦️ = 4 
🞹 =2

I have 7 A blocks so therefore I need:
▲ = 21
♦️ = 28
🞹 = 14

I did that for each block and separated the symbols for the background and coloured fabrics.

Background:

▲ = 174
D = 2
+   = 3
@  = 16
─ = 4

For the end triangles I am going to use a square/rectangle and cut them in half 

🞹 = 147 (or 74 squares)
▮ = 138 (or 69 rectangles)

Coloured Fabric:
⏺ = 50
♦️ = 153
⦚ = 12
>  = 4
# = 13

Swirl  = 41

Now knowing the amount, widths and lengths I once again opened trusty Microsoft Word

I have no idea if this makes sense to anyone else but I will try to explain.

The first measurements I factored in where the longest ones, I labelled these W, X and Y, they measure 72'' in length (the finished quilt being 70'' by 70''), which is obviously longer than 1 metre of fabric so I drew 2 metres (illustrated above by the blue square outlines)

I needed 2 W lengths which means I needed 5'' by 72'', I needed 8 X lengths which made it 8'' by 72'', 7 lengths of Y which made it 10.5'' by 72''

Which added together made in 23.5'' by 72'' (and I just noticed I made a mistake and fixed it, thank god I left a little extra just in case)

I had 20'' left which I used for my ▮ rectangle block - they are 5x8.5 so I fit 4 across and 8 down - measuring 20 by 68 (that gave me 32)

I carried on like that until I had all the right number of bit and I worked it out to be 3.5 meters (with not a lot spare) but considering I just found a mistake I'm going back to double check everything!
(I will be totally honest if I was wrong and make an edit at the bottom.)

I used the same method for the coloured fabric, this time using fat quarters instead of  meters of fabric.

As I have said before I want this quilt to look scrappy/colourful so instead of using a whole fat quarter I am only going to cut maybe 3 strips from each colour - I'll need about 26  different fat quarters colours.

Especially when it comes to the largest sizes e.g. I don't want 2 > the same colour or even a > and # from the same fabric.

Edit: 
Well I looked at it again and I did make a mistake
I think I gave myself to many rectangles and as that is the biggest size I only need 3 meters of fabric... Not sure I trust myself anymore!! Hopefully when I look at it again it will still add up the same!