1,4 . 15\49-(4\5 +2\3) : 2 trên 1\5
(4/5+2/3):2/1/5-1,4*15/49
(4/5+2/3):2/1/5-1,4*15/49
giúp mình với câu này kiểu đéo gì
1,4 . 15/49-(4/5+2/3):2/1/5
1,4 x 15/49 - (4/5+2/3) :2 và 1/5
a) 1,4 x 15/49-(4/5+2/3) : 2/1/5
1,4 . \(\dfrac{15}{49}\) - (\(\dfrac{4}{5}\) + \(\dfrac{-2}{3}\)) : \(2\dfrac{1}{5}\)
\(=\dfrac{7}{5}\cdot\dfrac{15}{49}-\left(\dfrac{4}{5}-\dfrac{2}{3}\right):\dfrac{11}{5}\)
\(=\dfrac{3}{7}-\dfrac{2}{15}\cdot\dfrac{5}{11}\)
\(=\dfrac{3}{7}-\dfrac{2}{33}=\dfrac{99-14}{33\cdot7}=\dfrac{85}{231}\)
\(1,4.\dfrac{15}{49}-[\dfrac{4}{5}+\dfrac{2}{3}]:2\dfrac{1}{5}\)
1,4 x 15/49 - ( 4/5 + 2/3 ) : 2 và 1/5
chú ý 2 và 1/5 là hỗn số
\(1,4x\frac{15}{49}-\left(\frac{4}{5}+\frac{2}{3}\right):2\frac{1}{5}\)
\(=\frac{3}{7}-\frac{22}{15}:2\frac{1}{5}\)
\(=\frac{3}{7}-\frac{2}{3}=-\frac{5}{21}\)
học tốt ~~~
\(1,4\times\frac{15}{49}-\left(\frac{4}{5}+\frac{2}{3}\right)\div2\frac{1}{5}\)
\(=\frac{14}{10}\times\frac{15}{49}-\frac{22}{15}\div\frac{11}{5}\)
\(=\frac{7}{5}\times\frac{15}{49}-\frac{22\times5}{15\times11}\)
\(=\frac{7\times15}{5\times49}-\frac{22\times5}{15\times11}\)
\(=\frac{7\times7\times3\times5}{5\times7\times7}-\frac{11\times2\times5}{3\times5\times11}\)
\(=3-\frac{2}{3}\)
\(=\frac{7}{3}\)
2/35 : (3/5+3/7)
1,2 . 25/6 - (4/3+5/3)
5 5/7 - (3/7+2 3/5) : 4/5
1,4 . 15/49 - (4/5+2/3) : 2 1/5
CÂU 1:\(\frac{2}{35}:\left(\frac{3}{5}+\frac{3}{7}\right)\)
\(=\frac{2}{35}:\frac{36}{35}\)
\(=\frac{1}{18}\)
CÂU 2:\(\frac{1}{2}\cdot\frac{25}{6}-\left(\frac{4}{3}+\frac{5}{3}\right)\)
\(=\frac{25}{12}-3\)
\(=-\frac{11}{12}\)
CÂU 3:\(5\frac{5}{7}-\left(\frac{3}{7}+2\frac{3}{5}\right):\frac{4}{5}\)
\(=\frac{40}{7}-\left(\frac{3}{7}+\frac{13}{5}\right):\frac{4}{5}\)
\(=\frac{40}{7}-\frac{106}{35}:\frac{4}{5}\)
\(=\frac{40}{7}-\frac{53}{14}\)
\(=\frac{27}{14}\)