How to Simplify Fractions with Brackets

[unknown1]

how do I work out this problem?19/20-(1/2-3/10)

 

[topsquark]

how do I work out this problem?19/20-(1/2-3/10)

With PEDMAS (or any of it's twins) you always start with what's inside the brackets. In this case
[math]\frac{1}{2} - \frac{3}{10}[/math]

Get a common denominator. In this case it is 10. So we have
[math]\frac{1}{2} \cdot \frac{5}{5} - \frac{3}{10} = \frac{5}{10} - \frac{3}{10}[/math]

Can you finish from here?

(As a slightly more advanced tip you might want to think about the common denominator of all three fractions. That would be 20.)

-Dan