Question

Answer 1

a)    \(\frac{7}{16}\) \(:\) \(\frac{3}{8}\) \(+\) \(\frac{9}{16}\) \(:\) \(\frac{3}{8}\)

  =       (  \(\frac{7}{16}\) \(+\) \(\frac{9}{16}\))   \(:\) \(\frac{3}{8}\)

  =                         \(1\)     \(.\)     \(\frac{8}{3}\)

  =                      \(\frac{3}{8}\)

Answer 2

b)   \(\frac{4}{21}\) \(:\) \(\frac{5}{7}\) \(-\) \(\frac{1}{7}\) \(:\) \(\frac{5}{7}\)

  =     (  \(\frac{4}{21}\) \(-\) \(\frac{1}{7}\))     \(:\) \(\frac{5}{7}\)

  =                  \(0\)        \(:\)     \(\frac{5}{7}\)

  =                              \(0\)

Answer 3

a)7/16 : 3/8 + 9/16 : 3/8 =(7/16 + 9/16) : 3/8 = 1 : 3/8 = 8/3

Answer 4

b)4/21 : 5/7 - 1/7 : 5/7 =(4/21 - 1/7) : 5/7 =1/21 : 5/7 =1/15

Answer 5

\(\frac{4}{9}\) \(.\) \(\frac{2}{3}\) \(.\) \(\frac{15}{8}\) \(:\)\(\frac{5}{4}\)

=    \(\frac{4}{9}\) \(.\) \(\frac{2}{3}\) \(.\) \(\frac{15}{8}\) \(.\) \(\frac{4}{5}\)

=    \(\frac{4}{9}\)  \(.\)  \(\frac{2.15.4}{3.8.5}\)

=     \(\frac{4}{9}\) \(.\) \(1\)

=       \(\frac{4}{9}\)

Answer 6

c. 4/9 x 2/3 x 15/8 : 5/4

= 8/27 x 15/8 : 5/4

=5/9 : 5/4

=4/9

Answer 7

200 x 120 =??? giúp mk với 

Answer 8

\(\frac{1}{2}\) \(.\) \(\frac{6}{7}\)\(+\) \(\frac{1}{4}\) \(.\) \(\frac{6}{7}\) \(+\) \(\frac{1}{8}\) \(.\) \(\frac{6}{7}\)

=     (  \(\frac{1}{2}\) \(+\) \(\frac{1}{4}\) \(+\) \(\frac{1}{8}\))    \(.\) \(\frac{6}{7}\)

=                 \(\frac{7}{8}\)   \(.\) \(\frac{6}{7}\)

=                  \(\frac{3}{4}\)

Answer 9

d. 1/2 x 6/7 + 1/4 x 6/7 + 1/8 x 6/7

= ( 1/2 + 1/4 + 1/8 ) x 6/7

=7/8 x 6/7

= 3/4

Answer 10

\(200\) \(.\) \(120\) =  \(24000\)

Answer 11

e. 23/14 x 6/13 - 9/14 x 6/13

= ( 23/14 - 9/14 ) x 6/13

= 1 x 6/13

= 6/13

Answer 12

200 x 120 = 24 000

Answer 13

câu cuối của tui đâu?

Answer 14

à quên có rồi xl nha

Answer 15

\(a.\frac{7}{16}:\frac{3}{8}+\frac{19}{16}:\frac{3}{8}\)

\(=\frac{7}{16}.\frac{8}{3}+\frac{19}{16}.\frac{8}{3}\)

\(=\frac{8}{3}\left(\frac{7}{16}+\frac{19}{16}\right)\)

\(=\frac{8}{3}.\frac{16}{16}\)

\(=\frac{8}{3}\)

\(b.\frac{4}{21}:\frac{5}{7}-\frac{1}{7}:\frac{5}{7}\)

\(=\left(\frac{4}{21}-\frac{1}{7}\right):\frac{5}{7}\)

\(=\frac{1}{21}:\frac{5}{7}\)

\(=\frac{1}{21}.\frac{7}{5}\)

\(=\frac{1}{15}\)

\(c.\frac{4}{9}.\frac{2}{3}.\frac{15}{8}:\frac{5}{4}\)

\(=\frac{4}{9}.\frac{2}{3}.\frac{15}{8}.\frac{4}{5}\)

\(=\frac{4}{9}.\frac{2}{3}.\frac{3}{2}\)

\(=\frac{4}{9}\)

\(d.\frac{1}{2}.\frac{6}{7}+\frac{1}{4}.\frac{6}{7}+\frac{1}{8}.\frac{6}{7}\)

\(=\frac{6}{7}\left(\frac{1}{2}+\frac{1}{4}+\frac{1}{8}\right)\)

\(=\frac{6}{7}\left(\frac{4+2+1}{8}\right)\)

\(=\frac{6}{7}.\frac{7}{8}\)

\(=\frac{6}{8}\)

\(=\frac{3}{4}\)

\(e.\frac{23}{14}.\frac{6}{13}-\frac{9}{14}.\frac{6}{13}\)

\(=\frac{6}{13}\left(\frac{23}{14}-\frac{9}{14}\right)\)

\(=\frac{6}{13}.1\)

\(=\frac{6}{13}\)