Question

[Tiểu Thư Hiền Hậu]

1 .Tính :

a . 4/5 + 3/7                  6/8 +4/2                      9/7 - 7/9                       8/7 - 7/8

b . 7/5 + 6/8 : 2/5                    3/2 - 2/3 +4/6                           6/7x 3/4- 4/3

Answer 1

[Đức Phạm]

a. \(\frac{4}{5}+\frac{3}{7}=\frac{28}{35}+\frac{15}{35}=\frac{43}{35}\)     ;   \(\frac{6}{8}+\frac{4}{2}=\frac{6}{8}+\frac{16}{8}=\frac{22}{8}=\frac{11}{4}\)

   \(\frac{9}{7}-\frac{7}{9}=\frac{81}{63}-\frac{49}{63}=\frac{32}{63}\);  \(\frac{8}{7}-\frac{7}{8}=\frac{64}{56}-\frac{49}{56}=\frac{15}{56}\)

b. \(\frac{7}{5}+\frac{6}{8}\div\frac{2}{5}=\frac{7}{5}+\frac{15}{8}=\frac{131}{40}\); \(\frac{3}{2}-\frac{2}{3}+\frac{4}{6}=\frac{5}{6}+\frac{4}{6}=\frac{9}{6}=\frac{3}{2}\)

\(\frac{6}{7}\times\frac{3}{4}-\frac{4}{3}=\frac{18}{28}-\frac{4}{3}=-\frac{29}{42}\)

Answer 2

[loan]

a) \(\frac{4}{5}+\frac{3}{7}=\frac{43}{35}\); \(\frac{6}{8}+\frac{4}{2}=\frac{11}{4}\)

\(\frac{9}{7}-\frac{7}{9}=\frac{32}{63}\) ; \(\frac{8}{7}-\frac{7}{8}=\frac{15}{56}\)

b) \(\frac{7}{5}+\frac{6}{8}:\frac{2}{5}=\frac{7}{5}+\frac{15}{8}=\frac{131}{40}\)

\(\frac{3}{2}-\frac{2}{3}+\frac{4}{6}=\frac{3}{2}\);\(\frac{6}{7}\times\frac{3}{4}-\frac{4}{3}=-\frac{23}{42}\)