Question

Thực hiện phép tính:

a. 7/-25 + -18/25 + 4/23 + 5/7 + 19/23

b. -2 + 15/19 + -15/17 +15/23 + 4/19

c. -5/11 + [-6/11 +1]

d. 1,4 . 15/49 - [4/5 + 2/3] : hai một phần năm

e. 7/19 .8/11 + 7/19 . 3/11 + 12/19

Answer 1

A.5/7

B.-481/391

C.0

D.-59/9

E.1

Answer 2

\(\dfrac{7}{-25}+\dfrac{18}{25}+\dfrac{4}{23}+\dfrac{5}{7}+\dfrac{19}{23}\)

=\(\left(\dfrac{-7}{25}+\dfrac{18}{25}\right)+\left(\dfrac{4}{23}+\dfrac{19}{23}\right)+\dfrac{5}{7}\)

= \(\dfrac{11}{25} +1+\dfrac{5}{7}\)

= \(1\dfrac{11}{25}+\dfrac{5}{7}\)

= \(2\dfrac{27}{175}\)

b) \(-2+\dfrac{15}{19}+\dfrac{-15}{17}+\dfrac{15}{23}+\dfrac{4}{19}\)

=\(-2+\left(\dfrac{ }{ }\right)\)