0 is freezing, 100 is boiling.

12 is a handy number but decimal calculation isn't difficult either, especially when all your units use the same.

What is a cup? How do you do calculations with a third of a cup etc?

I know a cup is roughly 200 mil. From exposure in life I know 200ml is about a cup of tea and 300ml is about a mug of coffee /can of come, 500 is a big can of beer. How many cups are in a can of beer?