Question

\(\frac{5}{7}.\frac{1}{3}-\frac{5}{7}.\frac{1}{4}-\frac{5}{7}.\frac{1}{2}\)

\(75\%-1\frac{1}{2}+0,5:\frac{5}{12}-\left(\frac{-1}{2}\right)^2\)

\(5\frac{2}{5}.4\frac{2}{7}+5\frac{5}{7}.5\frac{2}{5}\)

\(\frac{-7}{25}.\frac{11}{13}+\frac{-7}{25}.\frac{2}{13}-\frac{18}{25}\)

 

Answer 1

\(\frac{5}{7}\times\frac{1}{3}-\frac{5}{7}\times\frac{1}{4}-\frac{5}{7}\times\frac{1}{2}\)

\(=\frac{5}{7}\times\left(\frac{1}{3}-\frac{1}{4}-\frac{1}{2}\right)\)

\(=\frac{5}{7}\times\left(\frac{4}{12}-\frac{3}{12}-\frac{6}{12}\right)\)

\(=\frac{5}{7}\times\left(\frac{4-3-6}{12}\right)\)

\(=\frac{5}{7}\times\frac{-5}{12}\)

\(=\frac{5\times\left(-5\right)}{7\times12}\)

\(=\frac{-25}{84}\)

Answer 2

\(\frac{5}{7}.\frac{1}{3}-\frac{5}{7}.\frac{1}{4}-\frac{5}{7}.\frac{1}{2}\)

= \(\frac{5}{7}.\left(\frac{1}{3}-\frac{1}{4}-\frac{1}{2}\right).1\)

\(=\frac{5}{7}.\frac{-5}{12}\)

\(=-\frac{25}{84}\)

Answer 3

\(75\%-1\frac{1}{2}+0,5:\frac{5}{12}-\left(\frac{-1}{2}\right)^2\)

= \(\frac{3}{4}-\frac{3}{2}+\frac{1}{2}:\frac{5}{12}-\frac{1}{4}\)

\(\frac{3}{4}-\frac{3}{2}+\frac{1}{2}.\frac{5}{12}-\frac{1}{4}\)

\(\frac{3}{4}-\frac{3}{2}+\frac{5}{24}-\frac{1}{4}\)

\(\frac{18}{24}-\frac{36}{24}+\frac{5}{24}-\frac{6}{24}\)

-19/24

Answer 4

75 % =\(\frac{75}{100}\)-\(\frac{3}{2}\)+0.5 :\(\frac{5}{12}\)-\(\frac{1}{4}\)

=\(\frac{-3}{4}\)+1,2 - \(\frac{1}{4}\)

=0,45 - \(\frac{1}{4}\)

=0,2 hay \(\frac{1}{5}\)

Answer 5

\(75\%-1\frac{1}{2}+0,5:\frac{5}{12}-\left[\frac{-1}{2}\right]^2\)

\(=\frac{75}{100}-1\frac{1}{2}+\frac{5}{10}:\frac{5}{12}-\frac{1}{4}\)

\(=\frac{3}{4}-\frac{3}{2}+\frac{1}{2}:\frac{5}{12}-\frac{1}{4}\)

\(=\frac{3}{4}-\frac{3}{2}+\frac{1}{2}\cdot\frac{12}{5}-\frac{1}{4}\)

\(=\frac{3}{4}-\frac{3}{2}+\frac{1}{1}\cdot\frac{6}{5}-\frac{1}{4}\)

\(=\frac{3}{4}-\frac{3}{2}+\frac{6}{5}-\frac{1}{4}\)

\(=\frac{3}{4}-\frac{6}{4}+\frac{6}{5}-\frac{1}{4}=\left[\frac{3}{4}-\frac{6}{4}-\frac{1}{4}\right]+\frac{6}{5}=-1+\frac{6}{5}=\frac{1}{5}\)

Answer 6

Giúp Mik câu d

Answer 7

\(5\frac{2}{5}\cdot4\frac{2}{7}+5\frac{5}{7}\cdot5\frac{2}{5}\)

\(=5\frac{2}{5}\left[4\frac{2}{7}+5\frac{5}{7}\right]\)

\(=\frac{27}{5}\cdot10=54\)

Answer 8

\(\frac{-7}{25}\cdot\frac{11}{13}+\frac{-7}{25}\cdot\frac{2}{13}-\frac{18}{25}\)

\(=\frac{-7}{25}\cdot\left[\frac{11}{13}+\frac{2}{13}\right]-\frac{18}{25}\)

\(=\frac{-7}{25}\cdot1-\frac{18}{25}=\frac{-7}{25}-\frac{18}{25}=-1\)

Answer 9

\(5\frac{2}{5}.4\frac{2}{7}+5\frac{5}{7}\).\(5\frac{2}{5}\)

=\(\frac{27}{5}.\frac{30}{7}+\frac{40}{7}\)\(.\frac{27}{5}\)

=\(\frac{27}{5}.\left(\frac{30}{7}+\frac{40}{7}\right)\)

=\(\frac{27}{5}.\frac{70}{7}\)

=54