\(1\frac{1}{21}:\left(15,75-15\frac{1}{4}\right)+2\frac{1}{12}:-\left(7\frac{3}{4}-7,25\right)\)

ai làm đầy đủ giúp tớ nha

ai nhanh thì mình tick

tính

\(1\frac{1}{21}:\left(15,75-15\frac{1}{4}\right)+2\frac{1}{12}:\left(7\frac{3}{4}-7,25\right)\)

giúp ạ

\(tks\)

\(A=\left(6:\frac{3}{5}-1\frac{1}{6}x\frac{6}{7}\right):\left(4\frac{1}{5}x\frac{10}{11}+5\frac{2}{11}\right)\)\(B=\left(1-\frac{1}{2}\right)x\left(1-\frac{1}{4}\right)x.......x\left(1-\frac{1}{2015}\right)x\left(1-\frac{1}{2016}\right)\)

\(C=5\frac{9}{10}:\frac{3}{2}-\left(2\frac{1}{3}x4\frac{1}{2}-2x2\frac{1}{3}\right):\frac{7}{4}\)

1,Tính nhanh

a,3x\(\left(\frac{1}{7}+\frac{1}{3}-\frac{3}{14}\right):\frac{11}{14}\)

b,\(\left(\frac{21}{8}+\frac{1}{2}\right):\frac{5}{6}\)

3,Tìm x,biết

a,\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+......+\frac{2}{x\cdot\left(x+1\right)}=\frac{2016}{2018}\)

b,720:\(720:[41-\left(2\cdot x-5\right)]=120\)

Tính nhanh:

A=\(\left(\frac{2}{5}+\frac{2}{9}+\frac{2}{11}\div\frac{7}{5}+\frac{7}{9}+\frac{7}{11}\right)\div\left(\frac{1}{3}-\frac{1}{4}+\frac{1}{5}\div\frac{7}{6}-\frac{7}{8}+\frac{7}{10}\right)\)

bài 1

\(\frac{18}{11}+\left(\frac{7}{4}-\frac{3}{5}\right):\frac{1}{2}\)

\(\frac{8}{5}-\frac{1}{2}:\frac{1}{4}\cdot\left(\frac{3}{7}+\frac{1}{4}\right)\)

\(\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+\frac{1}{30}+\frac{1}{42}\)

Tính:

a,\(\frac{\left(3+\frac{1}{6}\right)-\frac{2}{5}}{\left(5-\frac{1}{6}\right)+\frac{7}{10}}\)

b,\(\frac{\left(4,08-\frac{2}{25}\right):\frac{4}{17}}{\left(6\frac{5}{9}-3\frac{1}{4}\right)x2\frac{2}{7}}\)

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

\(\left(1-\frac{1}{4}\right)\left(1-\frac{1}{9}\right)\left(1-\frac{1}{16}\right)\cdot....\cdot\left(1-\frac{1}{256}\right)\cdot x=\frac{108}{7}\)