Evaluate the parenthesis

To add $\frac{4}{5}$ and $\frac{1}{10}$, convert $\frac{4}{5}$ to a fraction with a denominator of 10: $\frac{4 \times 2}{5 \times 2} = \frac{8}{10}$. Then add: $\frac{8}{10} + \frac{1}{10} = \frac{9}{10}$.

$\frac{4}{5} + \frac{1}{10} = \frac{8+1}{10} = \frac{9}{10}$

Perform the division

Divide $\frac{9}{10}$ by the result of the parenthesis, which is $\frac{9}{10}$. Dividing by a fraction is the same as multiplying by its reciprocal.

$\frac{9}{10} \div \frac{9}{10} = \frac{9}{10} \times \frac{10}{9}$

Final Calculation

Cancel common factors in the numerator and denominator.

$\frac{9 \times 10}{10 \times 9} = 1$