Question

1- 1/10 + 7/10 = ?
2- 5/6 - 1/6 = ?​

Answer 1

Vamos lá.

mesmo denominador basta adicionar ou subtrair

1/10 + 7/10 = 8/10 = 4/5

5/6 - 1/6 = 4/6 = 2/3

Answer 2

1)

$\large\sf{} \dfrac{1}{10} + \dfrac{7}{10} \\ \\ \large\sf{} \dfrac{1 + 7}{10} \\ \\ \large\sf{} \dfrac{8}{10} \\ \\ \large\sf{} \frac{8 \div 2}{10 \div 2} \\ \\ {\large\boxed{\boxed{  { \large \sf \dfrac{4}{5} }}}}$

2)

$\large\sf{} \dfrac{5}{6} - \dfrac{1}{6} \\ \\ \large\sf{} \dfrac{5 - 1}{6} \\ \\ \large\sf{} \dfrac{4}{6} \\ \\ \large\sf{} \dfrac{4 \div 2}{6 \div 2} \\ \\{\large\boxed{\boxed{  { \large \sf \dfrac{2}{3} }}}}$

${\large\boxed{\boxed{  { \large \sf Bons~Estudos }}}}$