Câu 2: Trang 47 VNEN toán lớp 5 tập 1Tìm $x$:a. $x + \frac{3}{8}=\frac{4}{3}$ ...

a.
Cách 1:
$x + \frac{3}{8}=\frac{4}{3}$
$x = \frac{4}{3} - \frac{3}{8}$
$x = \frac{32}{24} - \frac{9}{24}$
$x = \frac{23}{24}$

Cách 2:
$x + \frac{3}{8} = \frac{4}{3}$
$x = \frac{4}{3} - \frac{3}{8}$
$x = \frac{32}{24} - \frac{9}{24}$
$x = \frac{23}{24}$

b.
Cách 1:
$x - \frac{4}{5} = \frac{7}{6}$
$x = \frac{7}{6} + \frac{4}{5}$
$x = \frac{35}{30} + \frac{24}{30}$
$x = \frac{54}{30}$

Cách 2:
$x - \frac{4}{5} = \frac{7}{6}$
$x = \frac{7}{6} + \frac{4}{5}$
$x = \frac{35}{30} + \frac{24}{30}$
$x = \frac{59}{30}$

c.
Cách 1:
$x \times \frac{1}{9} = \frac{21}{8}$
$x = \frac{21}{8} : \frac{1}{9}$
$x = \frac{21}{8} \times \frac{9}{1}$
$x = \frac{189}{8}$

Cách 2:
$x \times \frac{1}{9} = \frac{21}{8}$
$x = \frac{21}{8} : \frac{1}{9}$
$x = \frac{21}{8} \times \frac{9}{1}$
$x = \frac{189}{8}$

d.
Cách 1:
$x : \frac{8}{5} = 5$
$x = 5 \times \frac{8}{5}$
$x = \frac{40}{5}$
$x = 8$

Cách 2:
$x : \frac{8}{5} = 5$
$x = 5 \times \frac{8}{5}$
$x = \frac{40}{5}$
$x = 8$