\(a.\frac{-4}{11}.\frac{2}{5}+\frac{6}{11}.\frac{\left(-3\right)}{10}\)  

\(b.\left|\left(\frac{2}{3}-1\frac{1}{2}\right)\right|:\frac{4}{3}+\frac{1}{2}\)

\(c.\frac{1}{8}.15\frac{2}{5}+1\frac{4}{5}.\frac{1}{8}-17\frac{1}{5}.\frac{1}{8}\)

\(d.\frac{1}{7}-\frac{8}{7}:8-3:\frac{3}{4}.\left(-2^{ }\right)^2\)

Giúp mình nha . Cảm ơn các bạn !

Bài 1: Tính bằng cách hợp lí: 

a, \(11\frac{1}{4}-\left(2\frac{5}{7}+5\frac{1}{4}\right)\)

b, \(\left(8\frac{5}{11}+3\frac{5}{8}\right)-3\frac{5}{11}\)

c, \(-\frac{1}{4}.13\frac{9}{11}-0,25.6\frac{2}{11}\)

d, \(\frac{4}{9}:\left(-\frac{1}{7}\right)+6\frac{5}{9}:\left(-\frac{1}{7}\right)\)

Bài 2: Tính bằng cách hợp lí( nếu có)

a,\(\left(1,11+0,19-26\right):\left(2,06+0,54\right)-\left(\frac{1}{2}+\frac{1}{3}\right):2\)

b, \(\left(2\frac{1}{3}+3,5\right):\left(-4\frac{1}{6}+3\frac{1}{7}\right)+7,5\)

c, \(-15,5.20,8+3,5.9,2-15,5.9,2+3,5.20,8\)

Bài 3: Tìm x, biết:

a, \(\frac{2}{7}+x=20,75\)

b, \(-4\frac{1}{5}-x=2,25\)

c, \(x:8,5=2,2\)

d, \(\left(\frac{2x}{5}-1\right):\left(-5\right)=\frac{1}{7}\)

a) \(\left(\frac{11}{4}\cdot\frac{-5}{9}-\frac{4}{9}\cdot\frac{11}{4}\right)\cdot\frac{8}{33}\)

b) \(\frac{-1}{4}\cdot\frac{152}{11}+\frac{68}{4}\cdot\frac{-1}{11}\)

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

d) \(\left(\frac{1}{2}-1\right)\cdot\left(\frac{1}{3}-1\right)\cdot\left(\frac{1}{4}-1\right)\cdot....\cdot\left(\frac{1}{100}-1\right)\)

e) \(\frac{3}{2^2}\cdot\frac{8}{3^2}\cdot\frac{15}{4^2}\cdot...\cdot\frac{8^{99}}{30^2}\)

 \(A=\left(1\frac{1}{6}\times\frac{6}{7}\times6:\frac{3}{5}\right):\left(4\frac{1}{5}\times\frac{10}{11}+5\frac{2}{10}\right)\)

\(B=1\frac{13}{15}\times25\%\times3+\left(\frac{8}{15}-\frac{79}{60}\right):1\frac{23}{4}\)

\(C=\frac{123}{4567}\times\frac{1}{8}+\frac{123}{4567}\times\frac{1}{2}-\frac{123}{4567}\times\frac{13}{8}\)

\(D=\frac{10\frac{1}{3}\times\left(24\frac{1}{2}-15\frac{6}{7}\right)-\frac{12}{11}\times\left(\frac{10}{3}-1,75\right)}{\left(\frac{5}{9}-0,25\right)\times\frac{60}{11}+194\frac{8}{99}}\)

b3 tính nhanh nếu có thể

a \(\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}+\frac{1}{32}\)

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

c\(1\frac{1}{24}\cdot5\frac{2}{5}\cdot2-3\frac{7}{9}\cdot2\frac{2}{17}\)

d\(2\frac{3}{13}\cdot\frac{26}{58}\cdot4\cdot2\frac{15}{24}\cdot\frac{8}{21}\)

e \(\left(1-\frac{6}{11}\right)-\frac{5}{11}\)

f\(\left(\frac{15}{7}-\frac{2}{3}\right)+\frac{2}{3}\)

g\(\left(\frac{5}{8}-\frac{1}{4}\right)+\frac{3}{8}\)

\(h\frac{3}{3\cdot5}+\frac{3}{5\cdot8}+\frac{3}{8\cdot11}+\frac{3}{11\cdot14}+\frac{3}{14\cdot17}+\frac{3}{17\cdot20}\)

So sánh:

a, \(\frac{64}{85}\) và \(\frac{73}{81}\)

b, \(\frac{67}{77}\) và \(\frac{73}{83}\)

c, \(\frac{456}{461}\) và \(\frac{123}{128}\)

d, \(\frac{2015.2016-1}{2015.2016}\) và \(\frac{2016.2017-1}{2016.2017}\)

e, A= \(\frac{10^{12}-1}{10^{11}-1}\) và \(\frac{10^{11}+1}{10^{10}+1}\)

f, \(\left(\frac{1}{80}\right)^7\) và \(\left(\frac{1}{243}\right)^6\)

g, \(\left(\frac{3}{8}\right)^5\) và \(\left(\frac{5}{243}\right)^5\)