Mixed numbers bring in accuracy and in many many cases accuracy could be a question of life or death.
For example doctors use mixed numbers to find the right dose for a patient.
There are many many other examples. So in this video we will see how to do mixed number arithmetic.
Reference :
• Subtracting mixed numbers
https://www.sparknotes.com/math/preal...
https://www.mathsisfun.com/whole-numb...