Did it ever happen to you? You had someone over for coffee and you asked the person if he likes the coffee with milk and sugar. The answer was: „Milk please and half a spoon of sugar.“ And there you were trying to figure out how to make the coffee not to sweet.
Another example: According to a recipe you had to add half a spoon of something and you asked yourself how can I measure it right. Well, here is the answer, and it is simpler than you might think.