\(0,2+\dfrac{16}{21}-\dfrac{9}{5}+\dfrac{5}{21}\)
\(=\left(\dfrac{1}{5}-\dfrac{9}{5}\right)+\left(\dfrac{16}{21}+\dfrac{5}{21}\right)\)
\(=-\dfrac{8}{5}+1\)
\(=-\dfrac{3}{5}\)
\(1\dfrac{4}{25}+\dfrac{5}{21}-0,5+\dfrac{16}{21}\)
\(\left(1\dfrac{4}{23}-\dfrac{5}{21}\right)-\left(\dfrac{4}{23}-\dfrac{3}{4}\right)-\dfrac{16}{21}\)
Thực hiện phép tính (bằng cách hợp lý nếu có thể)
a) \(1\dfrac{4}{23}+\dfrac{5}{21}-\dfrac{4}{23}+0,5+\dfrac{16}{21}\)
b) \(\dfrac{3}{7}.19\dfrac{1}{3}-\dfrac{3}{7}.33\dfrac{1}{3}\)
c) \(9.\left(-\dfrac{1}{3}\right)^3+\dfrac{1}{3}\)
d) \(15\dfrac{1}{4}:\left(-\dfrac{5}{7}\right)-25\dfrac{1}{4}\left(-\dfrac{5}{7}\right)\)
1/ Tìm x,y biết:
a/ \(\dfrac{x}{2}\) = \(\dfrac{y}{5}\) và x+y=-21
b/ 7x = 3y và x-y=16
c/ \(\dfrac{x}{y}\) = \(\dfrac{5}{9}\) và 3x+2x=66
d/ \(\dfrac{x}{15}\) = \(\dfrac{y}{7}\) và x-2y=16
e/ \(\dfrac{x}{5}\) = \(\dfrac{y}{2}\) và x × y = 1000
2/ Tìm x,y,z biết
\(\dfrac{x}{13}\) = \(\dfrac{y}{7}\) = \(\dfrac{z}{5}\) và x-y-z=6
Giúp mình với ạ, mình xin cảm ơn trước ạ !.
\(\dfrac{5}{21}\) + \(\dfrac{1}{2}\) - \(\dfrac{19}{23}\) + \(\dfrac{16}{21}\) - \(\dfrac{4}{23}\)
a/ \(\dfrac{-3}{5}\) - x = \(\dfrac{21}{10}\)
b/ x : \(\dfrac{2}{9}\) = \(\dfrac{9}{2}\)
c/ \(\dfrac{x}{9}\) = \(\dfrac{5}{3}\)
d/ x : \(\left(\dfrac{2}{5}\right)^3\)= \(\left(\dfrac{5}{2}\right)^3\)
a/ \(\dfrac{-3}{5}\) - x = \(\dfrac{21}{10}\)
b/ x : \(\dfrac{2}{9}\) = \(\dfrac{9}{2}\)
c/ \(\dfrac{x}{9}\) = \(\dfrac{5}{3}\)
d/ x : \(\left(\dfrac{2}{5}\right)^3\)= \(\left(\dfrac{5}{2}\right)^3\)
giúp mik gấp nha, mik sắp thi rồi!
Tìm giá trị của biểu thức: \(B=x+\dfrac{0,2-0,375+\dfrac{5}{11}}{-0,3+\dfrac{9}{16}-\dfrac{15}{22}}vớix=-\dfrac{1}{3}\)
\(\dfrac{x-3}{3}=\dfrac{2x+1}{5}\)
\(\dfrac{x+1}{22}=\dfrac{6}{x}\)
\(\dfrac{2x-1}{2}=\dfrac{5}{x}\)
\(\dfrac{2x-1}{21}=\dfrac{3}{2x+1}\)
\(\dfrac{2x+1}{9}=\dfrac{5}{x+1}\)
Tìm x
