$a) \frac{2}{8} +x = \frac{9}{6}$
$⇒ x = \frac{9}{6} - \frac{2}{8}$
$⇒ x = \frac{5}{4}$
$Vậy$ $x = \frac{5}{4}$
$b) \frac{5}{8} +x = \frac{6}{8}$
$⇒ x = \frac{6}{8} - \frac{5}{8}$
$⇒ x = \frac{1}{8}$
$Vậy$ $x = \frac{1}{8}$
$c) x - \frac{3}{10} = \frac{4}{5}$
$⇒ x = \frac{4}{5} + \frac{3}{10} $
$⇒ x = \frac{11}{10} $
$Vậy$ $x = \frac{11}{10}$
$d) \frac{6}{10} ×x = \frac{6}{9} $
$⇒ x = \frac{6}{9} ÷ \frac{6}{10} $
$⇒ x = \frac{10}{9}$
$Vậy$ $x = \frac{10}{9}$
