a, 5\(\dfrac{4}{27}\) + \(\dfrac{6}{23}\) + 0,25 - \(\dfrac{4}{27}\) + \(\dfrac{17}{23}\)

= 5 +  (\(\dfrac{4}{27}\) - \(\dfrac{4}{27}\)) + (\(\dfrac{6}{23}\) + \(\dfrac{17}{23}\)) + 0,25

= 5 + 1 + 0,25

= 6,25

b, 16.(\(\dfrac{1}{2}\))³ - \(\dfrac{3}{5}\): 0,75

= 16.\(\dfrac{1}{8}\) - 0,8

= 2 - 0,8

= 1,2

\(a,\left(31\dfrac{6}{13}+5\dfrac{9}{41}\right)-36\dfrac{6}{13}\\ =\left(31-36\right)+\left(\dfrac{6}{13}-\dfrac{6}{13}\right)+5\dfrac{9}{41}\\ =-5+0+5\dfrac{9}{41}\\ =\left(-5+5\right)+\dfrac{9}{41}=\dfrac{9}{41}\)

\(b,\dfrac{5}{3}+\left(-\dfrac{2}{7}\right)-\left(-1,2\right)\\ =\dfrac{5}{3}-\dfrac{2}{7}+\dfrac{6}{5}\\ =\dfrac{5.35-2.15+6.21}{105}=\dfrac{271}{105}\\ c,0,25+\dfrac{3}{5}-\left(\dfrac{1}{8}-\dfrac{2}{5}+1\dfrac{1}{4}\right)=\dfrac{1}{4}+\dfrac{3}{5}-\dfrac{1}{8}+\dfrac{2}{5}-1\dfrac{1}{4}\\ =\left(-1\dfrac{1}{4}+\dfrac{1}{4}\right)+\left(\dfrac{3}{5}+\dfrac{2}{5}\right)-\dfrac{1}{8}=-1+1-\dfrac{1}{8}=-\dfrac{1}{8}\)

a) (31 6/13 + 5 9/41) - 36 6/13

= 409/13 + 214/41 - 474/13

= (409/13 - 474/13) + 214/41

= -5 + 214/41

= 9/41

b) 5/3 + (-2/7) - (-1,2)

= 5/3 - 2/7 + 6/5

= 29/21 + 6/5

= 271/105

c) 0,25 + 3/5 - (1/8 - 2/5 + 1 1/4)

= 1/4 + 3/5 - 1/8 + 2/5 - 5/4

= (1/4 - 5/4) + (3/5 + 2/5) - 1/8

= -1 + 1 - 1/8

= -1/8

a) \(=\left(\left(-\frac{1}{4}-\frac{5}{3}\right)+\frac{7}{33}\right)-\left(-\frac{15}{12}+\frac{6}{11}-\frac{48}{49}\right)\)

\(=\left(-\frac{23}{12}+\frac{7}{33}\right)+\frac{15}{12}-\frac{6}{11}+\frac{48}{49}\)

\(=\left(-\frac{23}{12}+\frac{15}{12}\right)+\left(\frac{9}{33}-\frac{6}{11}\right)+\frac{48}{49}\)

\(=-\frac{2}{3}-\frac{3}{11}+\frac{48}{49}\)

\(=\frac{65}{1617}\)

b) \(=\frac{11}{125}+\left(-\frac{17}{18}+\frac{4}{9}\right)+\left(-\frac{5}{7}+\frac{17}{14}\right)\)

\(=\frac{11}{125}-\frac{1}{2}+\frac{1}{2}\)

\(=\frac{11}{125}\)

tính từng cái là đc

a: \(5\cdot\frac{5}{27}+\frac{7}{23}+0,5\cdot\frac57+\frac{16}{23}+\frac12\)

\(=5\cdot\frac{5}{27}+\left(\frac{7}{23}+\frac{16}{23}\right)+0,5\left(\frac57+1\right)\)

\(=\frac{25}{27}+1+0,5\cdot\frac{12}{7}=\frac{25}{27}+1+\frac67=\frac{25}{27}+\frac{13}{7}=\frac{526}{27\cdot7}=\frac{526}{189}\)

b: \(25\frac16:\frac{-4}{5}-45\frac16:\frac{-4}{5}\)

\(=\left(25+\frac16-45-\frac16\right):\frac{-4}{5}\)

\(=-20\cdot\frac{-5}{4}=25\)

c: \(25\cdot\left(-\frac15\right)^3+\frac15-2\cdot\left(-\frac12\right)^2-\frac12\)

\(=25\cdot\frac{-1}{125}+\frac15-2\cdot\frac14-\frac12\)

\(=-\frac15+\frac15-\frac12-\frac12=-1\)

a: \(-\left(251\cdot3+281\right)+3\cdot251-\left(1-281\right)\)

\(=-251\cdot3-281+3\cdot251-1+281\)

=-1

b: \(\left(0,75-\frac14\right):\left(-5\right)+\frac{1}{15}-\left(-\frac15\right):\left(-3\right)\)

\(=\left(0,75-0,25\right):\left(-5\right)+\frac{1}{15}-\frac{1}{15}\)

=0,5:(-5)

=-1

c: \(\sqrt{\frac{4}{81}}:\sqrt{\frac{25}{81}}-1\frac25\)

\(=\frac29:\frac59-\frac75\)

\(=\frac25-\frac75=-\frac55=-1\)

a: \(-\left(251\cdot3+281\right)+3\cdot251-\left(1-281\right)\)

\(=-251\cdot3-281+3\cdot251-1+281\)

=-1

b: \(\left(0,75-\frac14\right):\left(-5\right)+\frac{1}{15}-\left(-\frac15\right):\left(-3\right)\)

\(=\left(0,75-0,25\right):\left(-5\right)+\frac{1}{15}-\frac{1}{15}\)

=0,5:(-5)

=-1

c: \(\sqrt{\frac{4}{81}}:\sqrt{\frac{25}{81}}-1\frac25\)

\(=\frac29:\frac59-\frac75\)

\(=\frac25-\frac75=-\frac55=-1\)

a: \(5\cdot\frac{5}{27}+\frac{7}{23}+0,5\cdot\frac57+\frac{16}{23}+\frac12\)

\(=5\cdot\frac{5}{27}+\left(\frac{7}{23}+\frac{16}{23}\right)+0,5\left(\frac57+1\right)\)

\(=\frac{25}{27}+1+0,5\cdot\frac{12}{7}=\frac{25}{27}+1+\frac67=\frac{25}{27}+\frac{13}{7}=\frac{526}{27\cdot7}=\frac{526}{189}\)

b: \(25\frac16:\frac{-4}{5}-45\frac16:\frac{-4}{5}\)

\(=\left(25+\frac16-45-\frac16\right):\frac{-4}{5}\)

\(=-20\cdot\frac{-5}{4}=25\)

c: \(25\cdot\left(-\frac15\right)^3+\frac15-2\cdot\left(-\frac12\right)^2-\frac12\)

\(=25\cdot\frac{-1}{125}+\frac15-2\cdot\frac14-\frac12\)

\(=-\frac15+\frac15-\frac12-\frac12=-1\)

Thực hiện phép tính ( bằng cách hợp lí nếu có thể ) 

A. 2/3 - (- 1/4)+3/5-(+7/45)-(-5/9)+1/12+1/39 

B. 6.(-2/3)^2 - 3(-2/3)^2 - 2 : (-3/2)+4