Hỗn số (tiếp theo)

Đổi \(9\dfrac{2}{3}m=\dfrac{29}{3}m\)

Chiều rộng là:

\(\dfrac{29}{3}\times\dfrac{1}{2}=\dfrac{29}{6}m\)

Chu vi là:

\(\left(\dfrac{29}{3}+\dfrac{29}{6}\right)\times2=29\left(m\right)\)

Diện tích là:

\(\dfrac{29}{3}\times\dfrac{29}{6}=\dfrac{841}{18}\left(m^2\right)\)

Vậy ...

??? ỦA HOK ĐỦ DỮ KIỆN

Chiều rộng:
`9 2/3 xx 1/2 = 29/6 = 4 5/6 m`

Chu vi:

`(4 5/6 + 9 2/3) xx 2 = 29 m`

Diện tích:

`29/6 xx 9 2/3 = 29/6 xx 29/2 = 841/12 m^2`

ok

làm đi

hay để tôi làm cho

\(x+3\dfrac{1}{5}=4\)

\(x+\dfrac{16}{5}=4\)

         \(x=4-\dfrac{16}{5}\)

         \(x=\dfrac{4}{5}\)

\(\left(x-\dfrac{2}{3}\right)\times3=\dfrac{3}{4}\)

       \(\left(x-\dfrac{2}{3}\right)=\dfrac{3}{4}:3\)

             \(x-\dfrac{2}{3}=\dfrac{1}{4}\)

                     \(x=\dfrac{1}{4}+\dfrac{2}{3}\)

                     \(x=\dfrac{11}{12}\)

     \(x+3\dfrac{1}{5}=4\)
=> \(x+\dfrac{16}{5}=4\)
     \(x\)           \(=4-\dfrac{16}{5}\)
     \(x\)           \(=\dfrac{20}{5}-\dfrac{16}{5}\)
     \(x\)           \(=\dfrac{4}{5}\)

\(\left(x-\dfrac{2}{3}\right) . 3=\dfrac{3}{4}\)
\(\left(x-\dfrac{2}{3}\right)\)     \(=\dfrac{3}{4} : 3\)
\(\left(x-\dfrac{2}{3}\right)\)     \(=\dfrac{3}{4} : \dfrac{3}{1}\)
\(\left(x-\dfrac{2}{3}\right)\)     \(=\dfrac{1}{4}\)
  \(x\)                \(=\dfrac{1}{4}+\dfrac{2}{3}\)
  \(x\)                \(=\dfrac{11}{12}\)
 

\(4\dfrac{1}{5}\)x\(2\dfrac{1}{4}=\)\(\dfrac{21}{5}\)x\(\dfrac{9}{4}\)\(=\dfrac{189}{20}\)

\(4\dfrac{1}{5}:2\dfrac{1}{4}=\dfrac{21}{5}:\dfrac{9}{4}=\dfrac{21}{5}\)x\(\dfrac{4}{9}\)=\(\dfrac{84}{45}=\dfrac{28}{15}\)

\(3\dfrac{3}{5}\)x\(1\dfrac{2}{3}=\)\(\dfrac{18}{5}\)x\(\dfrac{5}{3}=\)\(\dfrac{90}{15}=6\)

\(3\dfrac{3}{5}:1\dfrac{2}{3}=\dfrac{18}{5}:\dfrac{5}{3}=\dfrac{18}{5}\)x\(\dfrac{3}{5}=\)\(\dfrac{54}{25}\)

\(x:\dfrac{3}{5}=\dfrac{10}{3}\\ \Rightarrow x=\dfrac{10}{3}\times\dfrac{3}{5}\\ \Rightarrow x=\dfrac{10}{5}=2\)

\(x:\dfrac{3}{5}=3\dfrac{1}{3}=\dfrac{3\times3+1}{3}=\dfrac{10}{3}\)

\(x=\dfrac{10}{3}\times\dfrac{3}{5}=2\)

`x: 3/5 = 3 1/3`

`x : 3/5 = (3xx3+1)/3`

`x:3/5= 10/3`

`x= 10/3 xx 3/5`

`x= 30/15`

`x=2`

`x xx3=1 1/5`

`x xx 3= (1xx5+1)/5`

`x xx 3=6/5`

`x= 6/5 : 3`

`x= 6/5 xx 1/3`

`x= 6/15`

`x=2/5`

\(x\times3=1\dfrac{1}{5}\)
 

\(\xrightarrow[]{}x\times3=\dfrac{6}{5}\)
 

\(\xrightarrow[]{}x=\dfrac{6}{5}:3\)
 

\(\xrightarrow[]{}x=\dfrac{2}{5}\)

\(x\times3=1\dfrac{1}{5}=\dfrac{1\times5+1}{5}=\dfrac{6}{5}\)

\(x=\dfrac{6}{5}:3=\dfrac{6}{5\times3}=\dfrac{2}{5}\)

`3m 6 dm = 3 xx 10 = 30 + 6 = 36 dm = 3 6/10dm`

`7m 42cm = 7 xx 100 = 700 + 42 = 742 = 7 42/100 cm`

`5m 26 cm = 5 xx 100 = 500 + 26 = 526 = 5 26/100 cm`

Chu vi là: \(\left(2\dfrac{1}{4}+3\dfrac{1}{5}\right)\times2=\dfrac{109}{10}\left(m\right)\)

Diện tích là: \(2\dfrac{1}{4}\cdot3\dfrac{1}{5}=\dfrac{36}{5}\left(m^2\right)\)

Chu vi : \(2\dfrac{1}{4}+3\dfrac{1}{5}=\dfrac{2}{4}+\dfrac{3}{5}=\dfrac{10+12}{20}=\dfrac{22}{20}=\dfrac{11}{10}\left(m\right)\)

diện tích : \(2\dfrac{1}{4}x3\dfrac{1}{5}=\dfrac{2}{4}x\dfrac{3}{5}=\dfrac{3}{10}\left(m\right)\)

Đổi \(2\dfrac{1}{4}m=\dfrac{9}{4}m;3\dfrac{1}{5}m=\dfrac{16}{5}m\)

Chu vi mảnh đất là:

\(\left(\dfrac{9}{4}+\dfrac{16}{5}\right)\times2=\dfrac{109}{10}\left(m\right)\)

Diện tích mảnh đất là:

\(\dfrac{9}{4}\times\dfrac{16}{5}=\dfrac{36}{5}\left(m^2\right)\)

Vậy ...

`4 1/5 xx 2 1/4 = 21/5 xx 9/4 = 189/20`

`4 1/5 xx 2 1/4 = 21/5 : 9/4 = 21/5 xx 4/9 = 84/45`

`3 3/5 xx 1 2/3 = 18/5 xx 5/3  = 6`

`3 3/5 : 1 2/3 = 18/5 : 5/3 = 18/5 xx 3/5 =54/25`

\(3\dfrac{1}{4}-2\dfrac{1}{3}\)\(=\dfrac{13}{4}-\dfrac{7}{3}=\dfrac{39}{12}-\dfrac{28}{12}=\dfrac{11}{12}\)

\(6\dfrac{5}{9}+2\dfrac{5}{6}=\dfrac{59}{9}+\dfrac{17}{6}=\dfrac{354}{54}+\dfrac{153}{54}=\dfrac{507}{54}\)\(=\dfrac{169}{18}\)

\(6\dfrac{5}{9}-2\dfrac{5}{6}=\dfrac{59}{9}-\dfrac{17}{6}=\dfrac{354}{54}-\dfrac{153}{54}=\dfrac{67}{18}\)

`3 1/4 - 2 1/3 = 13/4 - 7/3 = 39/12 - 28/12 = 11/12`

`6 5/9 + 2 5/6 = 59/9 + 17/6 = 354/54 + 153/54 = 169/18`

`6 5/9 - 2 5/6 = 59/9 - 17/6 = 354/54 - 153/54 = 67/18`