# How do you simplify 9/10 - 1/5?

Aug 5, 2016

Find a common denominator, then subtract.

#### Explanation:

To find a common denominator, we need to find the least common multiple between the two denominators. In our case, the LCM (last common multiple) is 10 because $10 \cdot 1 = 10$ and $5 \cdot 2 = 10$. Our expression now looks like this:

$\frac{9}{10} - \frac{2}{10}$

From here, it's simple subtraction:

$9 - 2 = 7$

$\frac{9}{10} - \frac{2}{10} = \frac{7}{10}$