Question

(-3/4)+(2/7)+(-1/4)+(3/5)+(5/7) = ?

giúp em ạ

 

Answer 1

\(\left(\dfrac{-3}{4}\right)+\dfrac{2}{7}+\left(\dfrac{-1}{4}\right)+\dfrac{3}{5}+\dfrac{5}{7}=\left(\dfrac{-3}{4}+\dfrac{-1}{4}\right)+\left(\dfrac{2}{7}+\dfrac{5}{7}\right)+\dfrac{3}{5}=\left(-1\right)+1+\dfrac{3}{5}=0+\dfrac{3}{5}=\dfrac{3}{5}\)

Answer 2

`(-3 / 4 ) + 2 / 7 + (-1 / 4 ) + 3 / 5 + 5 / 7`

`= [ (-3 / 4 ) + (-1 / 4 ) ] + ( 2 / 7 + 5 / 7 ) + 3 / 5`

`= (-4 / 4) + 7 / 7 + 3 / 5`

`= (-1) + 1 + 3 / 5 = 3 / 5`

Answer 3

=3/5

Answer 4

= [(-3/4) + ( -1/4)] + [( 2/7) + (5/7)] + 3/5

= -1 + 1 + 3/5

= 3/5