Tìmx biết: a) x + 3/8 x 6/12 = 2 1/4 b) x – 5 3/4= 27/6 x 16/9 c) x x5 1/3 = 3 3/5 + 1 2/5 d) x : 1 2/7 + 2 =

Đáp án:

Giải thích các bước giải:

Tìm x :

a)

x + $\frac{3}{8}$ × $\frac{6}{12}$ = 2$\frac{1}{4}$

x + $\frac{3}{16}$ = $\frac{9}{4}$

x = $\frac{9}{4}$ – $\frac{3}{16}$

x = $\frac{33}{16}$

b)

x – 5$\frac{3}{4}$ = $\frac{27}{6}$ × $\frac{16}{9}$

x – $\frac{23}{4}$ = 8

x = 8 + $\frac{23}{4}$

x = $\frac{55}{4}$

c)

x × 5$\frac{1}{3}$ = 3$\frac{3}{5}$ + 1$\frac{2}{5}$

x × $\frac{16}{3}$ = $\frac{18}{5}$ + $\frac{7}{5}$

x × $\frac{16}{3}$ = 3

x = 3 : $\frac{16}{3}$

x = $\frac{9}{16}$

d)

x : 1$\frac{2}{7}$ + 2 = 3$\frac{8}{9}$

x : $\frac{9}{7}$ + 2 = $\frac{35}{9}$

x : $\frac{9}{7}$ = $\frac{35}{9}$ – 2

x : $\frac{9}{7}$ = $\frac{17}{9}$

x = $\frac{17}{9}$ × $\frac{9}{7}$

x = $\frac{51}{31}$