913 AND 784 KICK

a, (1+2+3+4+5+6+7)x37-123

=> 28x37-123=913

b, (2+7+9+5+6)x34-63+65

=> 29x34-63+65=988

474 chia hết cho 2,3

315 chia hết cho 3

7830 chia hết cho 5,9

Ai thấy mk đúng ủng hộ nha 

47 không chia hết cho 2 và 3

315 chia hết cho 3

783 không chia hết cho cả 5 và 9

474  chia hết cho 2 và 3

315 chia hết cho 3

7830 chia hết cho cả 5 và 9

\(\dfrac{7}{9}\)

\(\dfrac{43}{32}\)

\(\dfrac{1}{3}\)

\(\dfrac{45}{63}+\dfrac{28}{63}-\dfrac{24}{63}=\dfrac{49}{63}=\dfrac{7}{9}\)

\(\dfrac{31}{32}+\dfrac{11}{16}=\dfrac{31}{32}+\dfrac{22}{32}=\dfrac{43}{32}\)

\(\dfrac{5}{6}\times\dfrac{4}{3}-\dfrac{7}{9}=\dfrac{10}{9}-\dfrac{7}{9}=\dfrac{3}{9}=\dfrac{1}{3}\)

\(\frac{4}{5}\cdot\frac{3}{x}\cdot\frac{2}{11}=\frac{24}{165}\)

        \(\frac{3}{x}\)     \(=\frac{24}{165}:\frac{2}{11}:\frac{4}{5}\)

        \(\frac{3}{x}\)     \(=1\)

         \(x\)     \(=3\)

\(\frac{4}{3}:\frac{x}{5}=\frac{5}{13}\cdot\frac{4}{9}\)

\(\frac{4}{3}:\frac{x}{5}=\frac{20}{117}\)

      \(\frac{x}{5}=\frac{4}{3}:\frac{20}{117}\)

     \(\frac{x}{5}=\frac{39}{5}\)

     \(x=39\)

`a)4/5:3/x xx2/11=24/165`

`(4/5xx2/11)xx 3/x=8/55`

`8/55xx3/x=8/55`

`3/x=8/55:8/55`

`3/x=1`

`3:x=1`

`x=3:1`

`x=3`

____________________________________________

`b)4/3:x/5=5/13xx4/9`

`4/3:x/5=20/117`

`x/5=4/3:20/117`

`x/5=39/5`

`x=39`

A) 4/5:3/x X 2/11=24/165

\(\dfrac{4}{5}:\dfrac{3}{x}X\dfrac{2}{11}=\dfrac{24}{165}\)

\(\dfrac{3}{x}=\dfrac{24}{165}:\dfrac{4}{5}:\dfrac{2}{11}\)

\(\dfrac{3}{x}=1\)

\(\dfrac{3}{x}=\dfrac{3}{3}\)

=> x=3

B) \(\dfrac{4}{3}:\dfrac{x}{5}=\dfrac{5}{13}x\dfrac{4}{9}\)

\(\dfrac{4}{3}:\dfrac{x}{5}=\dfrac{20}{117}\)

\(\dfrac{x}{5}=\dfrac{4}{3}:\dfrac{20}{117}\)

\(\dfrac{x}{5}=\dfrac{39}{5}\)

=> x = 39

Cái này là Phương trình chứ cái j ???? 

\(y.9=783:3\)

\(\Leftrightarrow9y=261\)

\(\Leftrightarrow y=29\)

Vậy \(y=29\)