The last post this week takes a look at the last operation: subtraction. Fortunately, subtracting fractions is a lot like adding them. The denominator is still nothing more than a unit. We’re just manipulating the numerators.
For example:
This makes sense. If I have two thirds and you take one away, I’m left with only one third. Again, we’re making sure to call these fractions by their proper names so we remember those thirds are units, not numbers we have to work with.
Subtracting fractions with denominators also works the same way. You start by finding what both numbers go into and change both fractions accordingly. If I have to solve the problem 
Now that we have the same unit, we can do the subtraction:
Again, the denominator doesn’t change because it’s a unit instead of a number.
So, this concludes the look at simple fractions. Next week, we’re going to go back through the fraction skills with improper fractions and mixed numbers.
