\(\frac{x}{2}-\frac{11}{5}\)\(=\frac{7}{8}\times\frac{64}{49}\) ⇒\(\frac{x}{2}\) \(-\frac{11}{5}\)\(=\)\(\frac{8}{7}\) ⇒\(\frac{x}{2}=\frac{8}{7}+\frac{11}{5}\) ⇒\(\frac{x}{2}=\frac{117}{35}\) ⇒\(x=\frac{117}{35}\times2=\frac{234}{35}\)
\(\frac{x}{2}-\frac{11}{5}=\frac{7}{8}.\frac{64}{49}\)
=>
Thực hiện phép tính
\(a,(\frac{-5}{28}+1,75+\frac{8}{35}).(-3\frac{9}{20})\) \(b,(6-2\frac{4}{5}).3\frac{1}{8}-1\frac{3}{5}:\frac{1}{4}\)
\(c,(\frac{7-5}{24}+0,75+\frac{7}{12}):(-2\frac{1}{8})\) \(d,8\frac{2}{7}-(3\frac{4}{7}+4\frac{2}{7})\)
\(e,\left(-3,2\right).\frac{-15}{64}+(0,8-2\frac{4}{15}):3\frac{2}{3}\) \(f,1\frac{13}{15}.\left(0,5\right)^2.3+(\frac{8}{15}-1\frac{19}{60}):1\frac{23}{24}\)
\(g,1,4.\frac{15}{49}-(\frac{4}{5}+\frac{2}{3}):2\frac{1}{5}\)
Tính nhanh
\(5\frac{2}{7}.\frac{8}{11}\)+ \(5\frac{2}{7}.\frac{5}{11}\)-\(5\frac{2}{7}.\frac{2}{11}\)
Tính nhanh ( nếu có thể):
\(a,-3^2+\left\{-52:[\left(-3\right)^2\right\}\) \(d,(\frac{377}{-231}-\frac{123}{89}+\frac{34}{791}):(\frac{1}{6}-\frac{1}{8}-\frac{1}{24})\)
\(b,2\frac{3}{7}+(\frac{2}{9}-1\frac{3}{7})-\frac{5}{3}:\frac{1}{9}\) \(e,\frac{-5}{13}:\frac{3}{7}-\frac{2}{7}.\frac{8}{13}+\frac{5}{13}.\frac{1}{7}\)
\(c,\frac{-11}{23}.\frac{6}{7}+\frac{8}{7}.\frac{-11}{23}-\frac{1}{23}\)
Tìm x
a)\(5\frac{8}{17}:x+\left(-\frac{4}{7}\right)+3\frac{1}{7}:17\frac{1}{3}=\frac{4}{11}\)
b) \(\left(x+\frac{1}{5}\right)^2+\frac{17}{25}=\frac{26}{25}\)
1. tính nhanh
a) \(15\frac{3}{13}-\left(3\frac{4}{7}+8\frac{3}{13}\right)\)
b) \(\left(7\frac{4}{9}+4\frac{7}{11}\right)-3\frac{1}{2}\)
c) \(\frac{-7}{9}\times\frac{4}{11}+\frac{-7}{9}\times\frac{7}{11}+5\frac{7}{9}\)
Bài 1:Tìm x,biết
a) \(x-\frac{20}{11.13}-\frac{20}{13.15}-\frac{20}{15.17}-...-\frac{20}{53.55}=\frac{3}{11}\)
b)\(x+\frac{15}{90.94}+\frac{15}{94.98}+\frac{15}{98.102}+...+\frac{15}{146.150}=\frac{2}{3}\)
c)\(x-\frac{1}{2}-\frac{1}{6}-\frac{1}{12}-\frac{1}{20}-\frac{1}{30}-\frac{1}{42}-\frac{1}{56}=\frac{5}{24}\)
d)\(8-\frac{8-\frac{8}{5}+\frac{8}{25}-\frac{8}{125}}{9-\frac{9}{5}+\frac{9}{25}-\frac{9}{125}}:\frac{161616}{151515}=\frac{4+\frac{4}{73}-\frac{4}{115}}{5+\frac{5}{73}-\frac{1}{23}}\)
a) \(1-\left(5\frac{3}{8}+x-7\frac{5}{24}\right):\left(-16\frac{2}{3}\right)=0\)
b) \(\left(\frac{x}{3}-5\frac{1}{4}\right)^2-\frac{-2}{5}=1\frac{1}{25}\)
c) \(\frac{17-x}{12}=\frac{3}{17-x}\)
d) \(1\frac{1}{3}-25\%\left(x-\frac{8}{3}\right)+2x=1,6:\frac{3}{5}\)
A = \(\left(\frac{1}{4.9}+\frac{1}{9.14}+\frac{1}{14.19}+...+\frac{1}{44.49}\right).\frac{1-3-5-7-...-49}{89}\)
bài2
a, x+\(\frac{1}{6}=\frac{-3}{8}\)
b, \(\left[\frac{9}{2}-2x\right]\).\(\left[-1\frac{4}{7}\right]\)=\(\frac{11}{14}\)
