What is the difference between part to part ratio and a part to whole ratio ?

Ratios can be part-to-part, part-to-whole, or whole-to-part. Let's take a look at what this means.

When we compare boys to girls in a classroom, we are comparing part of the class to another part of the class. This would be a part-to-part comparison.

When we compare boys to the whole class, this is a part-to-whole comparison.

If we were to compare the class to the girls, this would be whole-to-part comparison.

EXAMPLE: A class is made up of 14 girls and 15 boys. 

PART_TO_PART 14 : 15 shows girls to boys

PART_TO_WHOLE 14: 29 shows girls to the class

Whole-to-Part 29 : 14 shows the class to the girls