Quote Originally Posted by KWF View Post
Is it mathematically correct to have a decimal as a numerator and one (1) as a denominator as in 0.5/1?
It is confusion about what is being measured by those numbers, and will likely cause thinking problems. Adding unit of measure can help:

1/2 car/passenger; 1 car per 2 passengers
1/2 mile/hour; 1 mile per 2 hours
1/2 milk/recipe; 1 milk per 2 recipes