a,{3849-2.[146-(2.14+6:2)]}.32

b,134-2.{156-6[54-2.(9+6)]}

c,\(\frac{5}{7}\).\(\frac{12}{11}\)+\(\frac{5}{7}\).\(\frac{17}{11}\)-\(\frac{5}{7}\).\(\frac{18}{11}\)+2\(\frac{1}{3}\)

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

e,\(\frac{1}{6}\)+\(\frac{1}{12}\)+\(\frac{1}{20}\)+\(\frac{1}{30}\)+\(\frac{1}{42}\)+\(\frac{1}{56}\)+\(\frac{1}{72}\)(Lưu ý chỉ phân số \(\frac{1}{72}\)mới có thể quy đồng)

+) A = ( 1,11 + 0,19 - 2,6 ) : ( 2,06 + 0,54 ) - ( \(\frac{1}{2}\) + \(\frac{1}{3}\) ) : 2

+) Tìm x :

a, (1,16 - x ) . 2,25 / 10 \(\frac{5}{9}\) - 7\(\frac{1}{4}\) . 2\(\frac{2}{11}\) = 75%

b) x + 25% .x = -1,25

c) x - 75% x = \(\frac{1}{4}\)

+) Tính nhanh nếu có thể :

a) 1\(\frac{1}{2}\) - 3\(\frac{3}{4}\) b) -8\(\frac{1}{6}\) - 7\(\frac{3}{2}\) c) 0,15 - 4,8 + 1,3 d) ( 2\(\frac{1}{3}\) + 3,5 ) : (-4\(\frac{1}{6}\) + 3\(\frac{1}{7}\) ) + 7,5

e) 11\(\frac{1}{4}\) + (2\(\frac{5}{7}\) + 5\(\frac{1}{4}\) ) f) \(\frac{4}{9}\) : ( \(\frac{1}{-7}\) + 6\(\frac{5}{9}\) :(-\(\frac{1}{7}\))

\(a,\frac{3}{4}-x=1\) \(b,x+4=\frac{1}{5}\) \(c,x-\frac{1}{5}=2\)

\(d,x+\frac{5}{3}=\frac{1}{81}\) \(e,x-\frac{10}{3}=\frac{7}{15}.\frac{3}{5}\) \(g,x+\frac{3}{22}=\frac{27}{121}.\frac{11}{9}\)

\(h,1-x=\frac{49}{65}.\frac{5}{7}\) \(i,\frac{8}{23}.\frac{46}{24}-x=\frac{1}{3}\) \(k,\frac{62}{7}.x=\frac{29}{9}:\frac{3}{56}\)

Bài 1 : Tính :

     a) A = \(\frac{\frac{3}{5}+\frac{3}{7}-\frac{3}{11}}{\frac{4}{5}+\frac{4}{7}+\frac{4}{41}}\)

     b) \(\frac{-1}{2}\)+ \(\frac{-2}{2}\) + \(\frac{-3}{4}\)

     c) C = \(\frac{\frac{2}{5}-\frac{2}{9}+\frac{2}{11}}{\frac{7}{5}-\frac{7}{9}+\frac{7}{11}}\) : \(\frac{\frac{1}{3}-\frac{1}{4}+\frac{1}{5}}{\frac{7}{6}-\frac{7}{8}+\frac{7}{10}}\)

Bài 2 : Tìm x , biết :

     a) \(\frac{1}{4}\) - \(\frac{1}{5}\) : x = \(\frac{3}{4}\)

     b) \(\frac{1}{7}\) . x - \(\frac{1}{5}\) + \(\frac{3}{4}\) = \(\frac{1}{2}\)

     c) \(\frac{3}{5}\) . x + \(\frac{1}{2}\) . x = \(\frac{3}{4}\)

     d) \(\frac{1}{3}\) . x - x = \(\frac{1}{5}\)

Bài 3 : Cho A = \(\frac{8}{9}\) . \(\frac{15}{16}\) . \(\frac{24}{25}\) . \(\frac{35}{36}\) . \(\frac{48}{49}\) . \(\frac{63}{64}\)

           và B = ( 1 - \(\frac{1}{3}\) ) . ( 1 - \(\frac{1}{6}\) ) . ( 1 - \(\frac{1}{10}\) ) . ( 1 - \(\frac{1}{15}\) ) . ( 1 - \(\frac{1}{21}\) )

       a) Tính A và B

       b) Tính \(\frac{1}{A}\) + \(\frac{1}{B}\)

Bài 1: 

A=0,7 . \(2\frac{2}{3}\). 20 . 0,375 . \(\frac{5}{28}\)

B=( 9,75 .\(21\frac{3}{7}\) + \(\frac{39}{4}\). \(18\frac{4}{7}\)) 

Bài 2

a)(x + \(\frac{1}{2}\)) . (\(\frac{2}{3}\)- 2x ) = 0

b)\(\frac{2}{3}x-\frac{1}{2}x=\frac{5}{12}\)

c) x .\(3\frac{1}{4}+\left(-\frac{7}{6}\right).x-1\frac{2}{3}=\frac{5}{12}\)

d)\(5\frac{8}{17}:x+\left(\frac{-4}{17}\right):x+3\frac{1}{7}:17\frac{1}{3}\)= \(\frac{4}{11}\)

1.tính nhanh nếu có thể

a)\(\frac{4}{11}\)-\(\frac{7}{15}\)+\(\frac{7}{11}\)-\(\frac{5}{15}\)

b)\(\frac{7}{3}\)-\(\frac{4}{9}\)-\(\frac{1}{3}\)-\(\frac{5}{9}\)

c)\((\frac{-1}{4}\)+\(\frac{7}{33}\)-\(\frac{5}{3}\)\()\)

d)\(\frac{-3}{4}\)\(\times\frac{8}{11}\)-\(\frac{3}{11}\)\(\times\frac{1}{2}\)

e)\(\frac{1}{15}\)+\(\frac{1}{35}+\frac{1}{63}+\frac{1}{99}+\frac{1}{143}+\frac{1}{195}\)

Thực hiện phép tính:

a) (\(\frac{3}{8}\)+ \(\frac{-3}{4}\)+ \(\frac{7}{12}\)) : \(\frac{5}{6}\)+ \(\frac{1}{2}\)

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

c) \(6\frac{5}{12}\): \(2\frac{3}{4}\)+ \(11\frac{1}{4}\). (\(\frac{1}{3}\)- \(\frac{1}{5}\))

d) (\(\frac{7}{8}\)- \(\frac{3}{4}\)) . \(1\frac{1}{3}\)- \(\frac{2}{7}\). (3,5)²

e) (\(\frac{3}{5}\)+ 0,415 - \(\frac{3}{200}\)) .\(2\frac{2}{3}\). 0,25

f) \(\frac{5}{16}\): 0,125 - (\(2\frac{1}{4}\)- 0,6) . \(\frac{10}{11}\)

g) 0,25 : (10,3 - 9,8) - \(\frac{3}{4}\)

h) \(1\frac{13}{15}\). 0,75 - (\(\frac{11}{20}\)+ 25%) : \(\frac{7}{3}\)

i) \(\frac{\left(\frac{1}{2}-0,75\right).\left(0,2-\frac{2}{5}\right)}{\frac{5}{9}-1\frac{1}{12}}\)

k) \(\frac{\frac{2}{3}+\frac{2}{7}-\frac{1}{14}}{-1-\frac{3}{7}+\frac{3}{28}}\)

Tính a) (4 \(\frac{5}{37}\)- 3\(\frac{4}{5}\)+8\(\frac{15}{29}\)) - (3\(\frac{5}{37}\)- 6\(\frac{14}{29}\)

b) 60 \(\frac{7}{13}\)x (8\(\frac{7}{10}\)) +50\(\frac{8}{13}\)x (-8 \(\frac{7}{10}\)) - 11 \(\frac{2}{13}\)x (-8 \(\frac{7}{10}\)

c) (2 \(\frac{5}{6}\)+ 1\(\frac{4}{9}\)) : ( 10 \(\frac{1}{2}\)- 9 \(\frac{1}{2}\)

d) 1 \(\frac{5}{18}\)- \(\frac{5}{18}\)x (\(\frac{1}{15}\)+1\(\frac{1}{12}\))

e)\(\frac{-1}{7}\)x (9 \(\frac{1}{2}\) - 8,75) :\(\frac{2}{7}\) +0,625 :1 \(\frac{2}{3}\)

TÍNH:

a) \(\frac{1}{12}\)+\(\frac{1}{20}\)\(\frac{1}{30}\)+\(\frac{1}{42}\)+\(\frac{1}{56}\)+\(\frac{1}{72}\)+\(\frac{1}{90}\)+\(\frac{1}{110}\)+\(\frac{1}{132}\)

b) (1-\(\frac{1}{7}\)).(1-\(\frac{1}{8}\)).(1-\(\frac{1}{9}\)) .... ( 1-\(\frac{1}{2011}\))

c) ( \(\frac{1}{10}\)-1).(\(\frac{1}{11}\)-1).(\(\frac{1}{12}\)-1) .... ( \(\frac{1}{2012}\)-1)

d) \(\frac{8^2}{7.9}\). \(\frac{9^2}{8.10}\).\(\frac{10^2}{9.11}\).\(\frac{11^2}{10.12}\).\(\frac{12^2}{11.13}\).\(\frac{13^2}{12.14}\).\(\frac{14^2}{13.15}\)