a, \(\dfrac{1}{2}\) - ( - \(\dfrac{1}{3}\) ) + \(\dfrac{1}{23}\) + \(\dfrac{1}{6}\)

 =  \(\dfrac{5}{6}\)  + \(\dfrac{1}{23}\) + \(\dfrac{1}{6}\)

= 1 + \(\dfrac{1}{23}\)

 = \(\dfrac{24}{23}\) 

b, \(\dfrac{11}{24}\) - \(\dfrac{5}{41}\) + \(\dfrac{13}{24}\) + 0,5 - \(\dfrac{36}{41}\)

= (\(\dfrac{11}{24}\) + \(\dfrac{13}{24}\)) - ( \(\dfrac{5}{41}\) + \(\dfrac{36}{41}\)) + 0,5

= 1 - 1 + 0,5

= 0,5 

c,\(-\dfrac{1}{12}-\left(\dfrac{1}{6}-\dfrac{1}{4}\right)\)

=\(-\dfrac{1}{12}-\left(-\dfrac{1}{12}\right)\)

=0

d, \(\dfrac{1}{6}-\left[\dfrac{1}{6}-\left(\dfrac{1}{4}+\dfrac{9}{12}\right)\right]\)

= \(\dfrac{1}{6}-\left[\dfrac{1}{6}-1\right]\)

= \(\dfrac{1}{6}-\left(-\dfrac{5}{6}\right)\)

= 1

e, 0,5 + \(\dfrac{1}{3}\) + 0,4 + \(\dfrac{5}{7}\) + \(\dfrac{1}{6}\) - \(\dfrac{4}{35}\)

 =    (0,5 + 0,4) + ( \(\dfrac{1}{3}\) + \(\dfrac{1}{6}\)) + (\(\dfrac{5}{7}\)  - \(\dfrac{4}{35}\))

 = 0,9 + \(\dfrac{1}{2}\) + \(\dfrac{3}{5}\)

= 0,9 + 0,5 + 0,6

= 2

\(\left[\frac{1}{33}+\frac{31}{333}-\left(\frac{341}{3333}\right)^2\right]\times\left(\frac{1}{2}-\frac{1}{3}-\frac{1}{6}\right)\)

=\(\left[\frac{1}{33}+\frac{31}{333}-\left(\frac{341}{3333}\right)^2\right]\times\left(\frac{3}{6}-\frac{2}{6}-\frac{1}{6}\right)\)

=\(\left[\frac{1}{33}+\frac{31}{333}-\left(\frac{341}{3333}\right)^2\right]\times\left(\frac{0}{6}\right)\)

=\(\left[\frac{1}{33}+\frac{31}{333}-\left(\frac{341}{3333}\right)^2\right]\times0\)

=0

a) \(0,6+\dfrac{2}{3}=\dfrac{6}{10}+\dfrac{2}{3}=\dfrac{3}{5}+\dfrac{2}{3}=\dfrac{9}{15}+\dfrac{10}{15}=\dfrac{19}{15}\)

b) \(-\dfrac{5}{12}+0,75=-\dfrac{5}{12}+\dfrac{75}{100}=-\dfrac{5}{12}+\dfrac{3}{4}=-\dfrac{5}{12}+\dfrac{9}{12}=\dfrac{4}{12}=\dfrac{1}{3}\)

c) \(\dfrac{1}{3}-\left(-0,4\right)=\dfrac{1}{3}+\dfrac{4}{10}=\dfrac{1}{3}+\dfrac{2}{5}=\dfrac{5}{15}+\dfrac{6}{15}=\dfrac{11}{15}\)

d) \(1\dfrac{3}{5}+\dfrac{5}{6}=\dfrac{8}{5}+\dfrac{5}{6}=\dfrac{48}{40}+\dfrac{25}{30}=\dfrac{73}{30}\)

11 3/4-[65/4-41/2]+1-2/3

47/4-[65/4-41/2]+1-2/3

47/4-(-17/4)+1-2/3

16/1+1-2/3

16/1+1/1-2/3

17/1-2/3

51/3-2/3

49/3

-3/4+3/4* (x-1/2)+1/6=-1

=0*(x-1/2)=-7/6

nên ko tìm đc x

Cách 1: 106 x (67 + 32) = 106 x 99 = 10494
Cách 2: 106 x (67 + 32) = 106 x 67 + 106 x 32 = 7102 + 3392 = 10494

đây nha 

Cách1 \(106\times\left(67+34\right)\)

\(106\times67+106\times34\)

\(=7102+3604\)\(=10706\)

cách 2 \(106\times\left(67+34\right)\)

\(=106\times101=10706\)

C1

78(27-16)=78x11=858

C2

78(27-16)=78x27-78x16=2106-1248=858

78 x (27-16) = 78 x 11 = 858

78 x (27-16) = (78 x 27) - (78x16) = 2106 - 1248 = 858