Fun Conversion Buttermilk Math

For safekeeping, we froze leftover buttermilk into an ice cube tray. 14 cubes.

Now I need 2 cups of buttermilk.

Weigh a glass using my trusty triple beam balance. 280g

Add two random cubes. 340g

Add two more. 400g

So it looks like each cube is 30g

And by this table of buttermilk equivalent values it looks like 2 cups is 480g.

SO I need 480/30 cubes, or 16 cubes. I only got 14. Close enough.

Melt them in the measuring cup. 1-3/4 cups. Top it off with milk. Done.