bài3

1. \(\frac{4}{3}\)= \(\frac{4x4}{3x4}\)=\(\frac{20}{12}\)

\(\frac{3}{4}\)=\(\frac{3x3}{4x3}\)=\(\frac{9}{12}\)

2.\(\frac{5}{4}\)=\(\frac{5x6}{4x6}\)=\(\frac{30}{24}\)

\(\frac{5}{6}\)=\(\frac{5x4}{6x4}\)=\(\frac{20}{24}\)

3.\(\frac{3}{8}\)=\(\frac{3x6}{8x6}\)=\(\frac{18}{48}\)

\(\frac{1}{6}\)=\(\frac{1x6}{6x8}\)=\(\frac{6}{48}\)

4.\(\frac{2}{5}\)=\(\frac{2x7}{5x7}\)=\(\frac{14}{35}\)

\(\frac{4}{7}\)=\(\frac{4x5}{7x5}\)=\(\frac{20}{35}\)

TL

Phân số là 3/45/4

HT

Bài 3 : 

a: \(MSC:12\\ \dfrac{4}{3}=\dfrac{4\times4}{3\times4}=\dfrac{16}{12};\dfrac{3}{4}=\dfrac{3\times3}{3\times4}=\dfrac{9}{12}\)

b: \(MSC:12\\ \dfrac{5}{4}=\dfrac{5\times3}{4\times3}=\dfrac{15}{12};\dfrac{5}{6}=\dfrac{5\times2}{6\times2}=\dfrac{10}{12}\)

c:\(MSC:24\\ \dfrac{3}{8}=\dfrac{3\times3}{8\times3}=\dfrac{9}{24};\dfrac{1}{6}=\dfrac{1\times2}{6\times2}=\dfrac{2}{12}\)

d: \(MSC:35\\ \dfrac{2}{5}=\dfrac{2\times7}{5\times7}=\dfrac{14}{35};\dfrac{4}{7}=\dfrac{4\times5}{7\times5}=\dfrac{20}{35}\)

Bài 3: 

a: 4/3=16/12

3/4=9/12

b: 5/4=30/24

5/6=20/24

c: 3/8=18/48

1/6=8/48

d: 2/5=14/35

4/7=20/35

Bài 4: 

a: 7/12=28/48

5/48=5/48

b: 4/100=4/100

8/25=32/100

a: 3/4=54/72

-1/9=-8/72

-5/8=-45/72

b: -1/7=-8/56

1/8=7/56

3/4=42/56

c: 1/3=10/30

-1/5=-6/30

-1/10=-3/30

a)\(\dfrac{3}{4}=\dfrac{3.18}{4.18}=\dfrac{54}{72}\)

\(\dfrac{1}{-9}=\dfrac{-1}{9}=\dfrac{-1.8}{9.8}=\dfrac{-8}{72}\)

\(\dfrac{-5}{8}=\dfrac{-5.9}{8.9}=\dfrac{-45}{72}\)

b)\(\dfrac{1}{-7}=\dfrac{-1}{7}=\dfrac{-1.8}{7.8}=\dfrac{-8}{56}\)

\(\dfrac{-1}{-8}=\dfrac{1}{8}=\dfrac{1.7}{8.7}=\dfrac{7}{56}\)

\(\dfrac{3}{4}=\dfrac{3.14}{4.14}=\dfrac{42}{56}\)

c)\(\dfrac{1}{3}=\dfrac{1.10}{3.10}=\dfrac{10}{30}\)

\(\dfrac{-1}{5}=\dfrac{-1.6}{5.6}=\dfrac{-6}{30}\)

\(\dfrac{1}{-10}=\dfrac{-1}{10}=\dfrac{-1.3}{10.3}=\dfrac{-3}{30}\)

giúp mình đi mà

mình xin đấy, mình đang cần gấp mà mọi người hông trả lời

a: 4/3=32/24

5/8=15/24

b: 4/5=36/45

5/9=25/45

c: 4/9=16/36

7/12=21/36

d: 1/2=6/12

2/3=8/12

7/12=7/12

4/3 và 5/8 

\(\dfrac{4}{3}=\dfrac{4x8}{3x8}=\dfrac{32}{24}\)

 \(\dfrac{5}{8}=\dfrac{5x3}{8x3}=\dfrac{15}{24}\)

4/5 và 5/9 

\(\dfrac{4}{5}=\dfrac{4x9}{5x9}=\dfrac{36}{45}\)

\(\dfrac{5}{9}=\dfrac{5x5}{9x5}=\dfrac{25}{45}\)

4/9 và 7/12 

  \(\dfrac{4}{9}=\dfrac{4x12}{9x12}=\dfrac{48}{108}\)

\(\dfrac{7}{12}=\dfrac{7x9}{12x9}=\dfrac{63}{108}\)

1/2 ; 2/3 và 7/12 

\(\dfrac{1}{2}=\dfrac{1x6}{2x6}=\dfrac{6}{12}\)

\(\dfrac{2}{3}=\dfrac{2x4}{3x4}=\dfrac{8}{12}\)

\(\dfrac{7}{12}=\dfrac{7x1}{12x1}=\dfrac{7}{12}\)

1/6,2/6,3/6,4/6,5/6...

3/24,5/24,7/24,9/24,11/24...

4/20,5/20,6/20,7/20...

8/30,9/30,10/30,11/30..

\(\frac{5}{3}=\frac{5\cdot4}{3\cdot4}=\frac{20}{12};\frac{1}{4}=\frac{1\cdot3}{4\cdot3}=\frac{3}{12}\)

\(\frac{3}{8}=\frac{3\cdot3}{8\cdot3}=\frac{9}{24};\frac{7}{24}\) 

\(\frac{1}{2}=\frac{1\cdot15}{2\cdot15}=\frac{15}{30};\frac{2}{3}=\frac{2\cdot10}{3\cdot10}=\frac{20}{30};\frac{3}{5}=\frac{3\cdot6}{5\cdot6}=\frac{18}{30}\)