Question

Tính gá trị của biểu thức 

5/7+4/9-8/21

7/8x3/4+11/16

5/6:3/4-7/9

Answer 1

\(\dfrac{7}{9}\)

\(\dfrac{43}{32}\)

\(\dfrac{1}{3}\)

Answer 2

\(\dfrac{45}{63}+\dfrac{28}{63}-\dfrac{24}{63}=\dfrac{49}{63}=\dfrac{7}{9}\)

\(\dfrac{31}{32}+\dfrac{11}{16}=\dfrac{31}{32}+\dfrac{22}{32}=\dfrac{43}{32}\)

\(\dfrac{5}{6}\times\dfrac{4}{3}-\dfrac{7}{9}=\dfrac{10}{9}-\dfrac{7}{9}=\dfrac{3}{9}=\dfrac{1}{3}\)