Question

Câu 1: 

\(\dfrac{13}{15}\). 0,75 - (\(\dfrac{9}{20}\) + 25% ) : 1\(\dfrac{2}{5}\)

Câu 2:

a, \(\dfrac{3}{2}\) - x = \(\dfrac{4}{9}\)

b, \(\dfrac{x}{3}\)+ 2  \(\dfrac{3}{7}\)= \(\dfrac{-5}{2}\)

 

Answer 1

Câu 1:

\(\dfrac{13}{15}\cdot0,75-\left(\dfrac{9}{20}+25\%\right):1\dfrac{2}{5}\)

\(=\dfrac{13}{15}\cdot\dfrac{3}{4}-\left(0,45+0,25\right):\dfrac{7}{5}\)

\(=\dfrac{13}{20}-0,7\cdot\dfrac{5}{7}\)

\(=0,65-0,5=0,15\)

Câu 2:

a: \(\dfrac{3}{2}-x=\dfrac{4}{9}\)

=>\(x=\dfrac{3}{2}-\dfrac{4}{9}=\dfrac{27}{18}-\dfrac{8}{18}=\dfrac{19}{18}\)

b: \(\dfrac{x}{3}+2\dfrac{3}{7}=-\dfrac{5}{2}\)

=>\(\dfrac{x}{3}+\dfrac{17}{7}=-\dfrac{5}{2}\)

=>\(\dfrac{x}{3}=-\dfrac{5}{2}-\dfrac{17}{7}=\dfrac{-69}{14}\)

=>\(x=-\dfrac{69}{14}\cdot3=-\dfrac{207}{14}\)