26,72 :18 + 63,28 :18=18:(26,72+ 63,28)

                                  =18:100

                                  =0,18

\(=\left(26,72+63,28\right):18=90:18=5\)

= ( 63,28 + 26,72 ) : 18

= 100 : 18

= \(\dfrac{50}{9}\)

`9/14+19/18+19/14+35/18`

`=(9/14+19/14)+(19/18+35/18)`

`=28/14+54/18`

`=2+3`

`=5`

   42 x 3 + 18 x 32 + 18 x 61

= 6 x 7 x 3 + 18 x 32 + 18 x 61

= 18 x 7 + 18 x 32 + 18  x 61

= 18 x (7 + 32 + 61)

= 18 x 100

= 1800

\(42\times3+18\times32+18\times61\)

\(=6\times7\times3+18\times32+18\times61\)

\(=18\times7+18\times32+18\times61\)

\(=18\times\left(7+32+61\right)\)

\(=18\times100\)

\(=1800\)

6 x 7 x 3 + 18 x 32 +18 x 61

18 x 7 + 18 x32 +18 x 61

18 x ( 7 + 32 + 61 )

18 x           100

1800

=9/4x2/3+16/9x4/3

=18/12+64/36

=54/36+64/36=118/36=59/18

 36/16 x 12/18 + 32/18 x 24/18 

\(=\dfrac{9}{4}\times\dfrac{2}{3}+\dfrac{16}{9}\times\dfrac{4}{3}\)

\(=\dfrac{3}{2}+\dfrac{64}{27}\)

\(=\dfrac{209}{54}\)

\(\frac{1}{15}+\frac{4}{15}+\frac{5}{18}+\frac{7}{18}\)

\(=\left(\frac{1}{15}+\frac{4}{15}\right)+\left(\frac{5}{18}+\frac{7}{18}\right)\)

\(=\frac{5}{15}+\frac{12}{18}\)

\(=\frac{1}{3}+\frac{2}{3}\)

\(=\frac{3}{3}=1\)

\(\frac{1}{15}+\frac{4}{15}+\frac{5}{18}+\frac{7}{18}\)

\(=\left(\frac{1}{15}+\frac{4}{15}\right)+\left(\frac{5}{18}+\frac{7}{18}\right)\)

\(=\frac{1}{3}+\frac{2}{3}\)

\(=1\)

\(\frac{1}{15}+\frac{4}{15}+\frac{5}{18}+\frac{7}{18}\)

\(=\left(\frac{1}{15}+\frac{4}{15}\right)+\left(\frac{5}{18}+\frac{7}{18}\right)\)

\(=\frac{5}{15}+\frac{12}{18}\)

\(=\frac{1}{3}+\frac{2}{3}\)

\(=\frac{3}{3}\)

\(\Rightarrow=1\)

18 x 24: 9

= 432 : 9 = 48

= ( 18 : 9) x 50

= 2 x 50

= 100

\(\left(50\times18\right):9\\ 50\times18:9\\ =50\times\left(18:9\right)\\ =50\times2\\ =100\)

(50 x 18) : 9 

= (18 : 9 ) x 50

= 2 x 50

= 100

4 x 18 x 25

= 18 x (4 x 25)

= 10 x 100 = 1800