Tìm x, biết: $\frac{3}{1.4}$x+$\frac{3}{4.7}$x+ $\frac{3}{7.10}$x+...+ $\frac{3}{31.34}$x=33

$\dfrac{3}{1.4}$$\text{x + $\dfrac{3}{4.7}$}$$\text{x + ... + $\dfrac{3}{31.33}$}$$\text{x = 33}$

$\Rightarrow$ $\text{x . (1 - $\dfrac{1}{4}$}$ $\text{+ $\dfrac{1}{4}$}$ $\text{- $\dfrac{1}{7}$}$ $\text{+ $\dfrac{1}{7}$}$ $\text{- $\dfrac{1}{10}$}$ $\text{+ ... + $\dfrac{1}{33}$}$ $\text{- $\dfrac{1}{34}$}$$\text{) = 33}$

$\Rightarrow$ $\text{x . (1 - $\dfrac{1}{34}$}$$\text{) = 33}$

$\Rightarrow$ $\text{x . $\dfrac{33}{34}$}$ $\text{= 33}$

$\Rightarrow$ $\text{x = 33 : $\dfrac{33}{34}$}$

$\Rightarrow$ $\text{x = 34}$

$\text{Vậy: x = 34}$