Question

Simplify :

$4\frac{6}{7}-2\frac{2}{3}-\frac{20}{21}$

Answer 1

$4\frac{6}{7}-2\frac{2}{3}-\frac{20}{21}=\frac{34}{7}-\frac{8}{3}-\frac{20}{21}$

We will find out the LCM of the denominators $7,3and21=21$

$$\begin{gathered} =\frac{34\times (21÷7)-8\times (21÷3)-20\times (21÷21)}{21} \\ =\frac{34\times 3-8\times 7-20\times 1}{21} \\ =\frac{102-56-20}{21} \\ =\frac{102-76}{21} \\ =\frac{26}{21} \end{gathered}$$

Therefore the required answer after simplification is $\frac{26}{21}$