Meijer and Walmart store brands of cheap ass white bread are 22 slices, Kroger is 21, and for a name brand example Sunbeam is 22. Nicer bread like Pepperidge Farm or Brownberry/Oroweat tends to be in the range of 16 slices per loaf (baring the thin sliced stuff) though.
Ternary plots (aka Triangle plots) have three axes rotated and layered on top of each other. So when you get a point like this:
You read it as 50% of the way up the clay direction:
30% of the way up the sand direction:
20% of the way up the silt direction:
So it is 50% clay, 30% sand, and 20% silt.