(\(\dfrac{9}{25}\) - 2.18) : (\(\dfrac{19}{5}\) + 0,2)

=(\(\dfrac{9}{25}\) - 2.18) : (\(\dfrac{19}{5}\) +\(\dfrac{1}{5}\) )

=(\(\dfrac{9}{25}\)- 36) : 4

=\(\dfrac{-117}{5}\) : 4

= \(\dfrac{-117}{20}\)

(\(\dfrac{9}{25}\)-2.18) : (\(\dfrac{19}{5}\) +0,2)

= (\(\dfrac{9}{25}\)- 2.18) : (\(\dfrac{19}{5}\)+\(\dfrac{1}{5}\))

= (\(\dfrac{9}{25}\)-36): 4

= \(\dfrac{-891}{25}\):4

=\(\dfrac{-891}{100}\)

\((\frac{9}{25}-2.18):\left(3\frac{4}{5}-0,2\right)\)

=-1,82 : 4

=-0,455

\(\left(\frac{9}{25}-2.18\right):\left(3\frac{4}{5}-0,2\right)\)

= -1,82:4=-0,455

\(\left(\frac{9}{15}-2,18\right):\left(3\frac{4}{5}+0,2\right)=\left(0,6-2,18\right):\left(3,8+0,2\right)=-1,58:4=-0,395\)

= -8,91             

\(\dfrac{5}{3}\cdot\dfrac{7}{25}+\dfrac{5}{3}\cdot\dfrac{21}{25}-\dfrac{5}{3}\cdot\dfrac{7}{25}\)

\(=\dfrac{5}{3}\cdot\left(\dfrac{7.}{25}+\dfrac{21}{25}-\dfrac{7}{25}\right)\)

\(=\dfrac{5}{3}\cdot\dfrac{21}{25}=\dfrac{7}{5}\)

b) \(250\%+19\dfrac{3}{11}\cdot\dfrac{7}{26}-6\dfrac{3}{11}\cdot\dfrac{7}{26}\)

\(=\dfrac{5}{2}+\dfrac{212}{11}\cdot\dfrac{7}{26}-\dfrac{69}{11}\cdot\dfrac{7}{26}\)

\(=\dfrac{7}{26}\cdot\left(\dfrac{212}{11}-\dfrac{69}{11}\right)+\dfrac{5}{2}\)

\(=\dfrac{7}{26}\cdot13+\dfrac{5}{2}\)

\(=\dfrac{7}{2}+\dfrac{5}{2}\)

\(=\dfrac{12}{2}=6\)

(1-3)+(5-7)+(9-11)+....+(17-19)

=(-2)+(-2)+(-2)+...+(-2)

=(-2)x5

=-10

a) \(=-\frac{91}{50}:4\)

   \(=-\frac{91}{200}\)

b) \(=\frac{5}{18}-\frac{26}{5}+\frac{18}{5}\)

   \(=-\frac{119}{90}\)

\(\left(\frac{9}{25}-2,18\right):\left(3\frac{4}{5}+0,2\right)\)

\(=\left(-1,82\right):4\)

\(=-0,455\)

\(\dfrac{4}{5}\)+\(\dfrac{-5}{4}\)=\(\dfrac{0}{4}\)

\(\dfrac{-1}{3}\)+\(\dfrac{2}{5}-\dfrac{5}{6}\)=\(\dfrac{-10}{30}+\dfrac{12}{30}-\dfrac{25}{30}\)=\(\dfrac{-23}{30}\)

\(\dfrac{2}{3}-\dfrac{5}{7}.\dfrac{14}{25}\)=\(\dfrac{2}{3}-\dfrac{2}{5}\)=\(\dfrac{10}{15}-\dfrac{6}{15}\)=\(\dfrac{4}{15}\)

a: \(=\dfrac{16-25}{20}=\dfrac{-9}{20}\)

b: \(=\dfrac{-10}{30}+\dfrac{12}{30}-\dfrac{25}{30}=-\dfrac{23}{30}\)

c: \(=\dfrac{2}{3}-\dfrac{1}{5}\cdot2=\dfrac{2}{3}-\dfrac{2}{5}=\dfrac{10-6}{15}=\dfrac{4}{15}\)

d: \(=\dfrac{12-25}{30}\cdot\dfrac{15}{8}-1=\dfrac{-13}{16}-1=\dfrac{-29}{16}\)

e: \(=\dfrac{-3}{13}-\dfrac{10}{13}-\dfrac{7}{17}+\dfrac{24}{17}-\dfrac{5}{19}-\dfrac{14}{19}=-1\)

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