Bài 1: Thực hiện phép tính(tính nhanh nếu có thể)

a) \(\frac{-4}{5}:\frac{8}{7}\)

b) \(\frac{-3}{8}.\frac{7}{9}+\frac{-3}{8}.\frac{2}{9}+0,25\)

c) 15\(\frac{3}{7}-\left(2\frac{4}{9}+11\frac{3}{7}\right)\)

Bài 2: Tìm x, biết:

a) x+\(\frac{2}{3}=\frac{5}{6}\)

b) 2\(\frac{3}{5}-8x=\left(\frac{1}{7}-\frac{1}{8}\right).56\)

Tính (Tính nhanh nếu có thể)

\(a,7\frac{3}{4}:5-15.0,025+\frac{3}{14}.\left(-0,7\right)\)

\(b,\frac{-11}{5}+\frac{5}{17}.\left(6\frac{1}{3}-5\frac{1}{5}\right)-1\frac{11}{15}\)

\(c,\frac{-3}{7}.\frac{5}{9}+\frac{4}{9}.\frac{-3}{7}=2\frac{3}{7}\)          = là +

\(d,0,5.1\frac{1}{3}.75\%:\frac{2}{5}+\frac{3}{5}\)

\(e,\left(\frac{2}{3}+\frac{2}{7}-\frac{1}{14}\right):\left(-1-\frac{3}{7}+\frac{3}{28}\right)\)

bài 1 thực hiện phép tính, tính nhanh nếu có thể

a, \(\frac{-11}{23}.\frac{6}{7}+\frac{8}{7}.\frac{-11}{23}-\frac{1}{23}\)

b,\(0,75.1\frac{7}{9}-1\frac{2}{5}:\frac{-21}{20}\)

c,\(2.\frac{3}{7}+\left(\frac{2}{9}-1\frac{3}{7}\right)-\frac{5}{3}:\frac{1}{9}\)

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

e,\(\left(6-2\frac{4}{5}\right).3\frac{1}{8}-1\frac{3}{5}:25\%\)

g,\(0,2.\frac{15}{36}-\left(\frac{2}{5}+\frac{2}{3}\right):1\frac{1}{5}\)

h,\(2\frac{1}{3}-\frac{1}{3}.\left(\frac{-3}{2}+\left(\frac{2}{3}+0,4.5\right)\right)\)

i,\(\frac{1}{3}.\frac{5}{7}-\frac{7}{27}.\frac{36}{14}\)

k,\(\left(\frac{-5}{28}+1,75+\frac{8}{35}\right):\left(-3\frac{9}{20}\right)\)

l,\(\left(20+9\frac{1}{4}\right):2\frac{1}{4}\)

m,\(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+...+\frac{1}{12.13}\)

n,\(\frac{5}{1.3}+\frac{5}{3.5}+\frac{5}{5.7}+...+\frac{5}{99.101}\)