= 1*9 + 11.(11 + 1) : 2

= 9 + 66 = 75 

bằng 75 nha

75 – 8 + 6 = 67 ( sai vì 75 – 8 + 6 = 63)

39 + 17 – 8 = 48 ( đúng vì 39 + 17 – 8 = 48)

34+67-67+67-67 x 1 = 34

34 nhé

67 kg + 7 kg =74 kg

29 kg + 4 kg =33kg

46 l + 8 l =54l

6 l + 59 l =65l

67 kg + 7 kg = 74 kg

29 kg + 4 kg = 33 kg

46 l + 8 l = 54 l

6 l + 59 l = 65 l

\(\begin{array}{*{20}{c}}{a)\,\,}\\{}\\{}\end{array}\begin{array}{*{20}{c}}{ + \begin{array}{*{20}{c}}{536}\\{\,\,\,\,\,8}\end{array}}\\\hline{\,\,\,544}\end{array}\)                           \(\begin{array}{*{20}{c}}{ + \begin{array}{*{20}{c}}{\,\,\,67}\\{829}\end{array}}\\\hline{\,\,\,\,996}\end{array}\)                            \(\begin{array}{*{20}{c}}{ + \begin{array}{*{20}{c}}{432}\\{284}\end{array}}\\\hline{\,\,\,\,716}\end{array}\)

\(\begin{array}{*{20}{c}}{b)\,\,}\\{}\\{}\end{array}\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{253}\\{\,\,\,\,\,7}\end{array}}\\\hline{\,\,\,\,246}\end{array}\)                     \(\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{561}\\{\,\,\,42}\end{array}}\\\hline{\,\,\,519}\end{array}\)                             \(\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{795}\\{638}\end{array}}\\\hline{\,\,\,\,057}\end{array}\)

a,23+45+67+89                             

=68+67+89      

=135+89

=224

b,345-123+700+8

=222+700+8

=922+8

=930

c,7x8x9x10+345678:0,5

=5040+691356

=696396

67+67=134 nhé

=134 nha ban