\(MSC:72\)

\(\dfrac{9}{12}=\dfrac{9\times6}{12\times6}=\dfrac{54}{72}\)

\(\dfrac{24}{36}=\dfrac{24\times2}{36\times2}=\dfrac{48}{72}\)

\(\dfrac{3}{8}=\dfrac{3\times9}{8\times9}=\dfrac{27}{72}\)

9/12=36/48

24/36=2/3=32/48

3/8=18/48

a) \(\dfrac{6}{7}=\dfrac{6\times11}{7\times11}=\dfrac{66}{77}\)  ;   \(\dfrac{5}{11}=\dfrac{5\times7}{11\times7}=\dfrac{35}{77}\)

b) \(\dfrac{5}{9}=\dfrac{5\times5}{9\times5}=\dfrac{25}{45}\)    ;   \(\dfrac{9}{5}=\dfrac{9\times9}{5\times9}=\dfrac{81}{45}\)

c) \(\dfrac{3}{8}=\dfrac{3\times3}{8\times3}=\dfrac{9}{24}\)    ;    \(\dfrac{5}{24}\) giữ nguyên phân số

d) \(\dfrac{6}{5}=\dfrac{6\times6}{5\times6}=\dfrac{36}{30}\)    ;     \(\dfrac{5}{6}=\dfrac{5\times5}{6\times5}=\dfrac{25}{30}\)

\(#Wendy.Dang\)

a) 6/7 và 5/11

ta có :

6/7=66/77

5/11=35/77

b)5/9 và 9/5

ta có 

5/9=25/45

9/5=81/45

C)3/8 và 5/24

ta có :

3/8=9/24

5/24

D)6/5 và 5/6

ta có 

6/5=36/30

5/6=25/30

\(1,\\ \dfrac{3}{5}=\dfrac{21}{35};\dfrac{4}{7}=\dfrac{20}{35}\\ \dfrac{2}{3}=\dfrac{4}{6};\dfrac{5}{6}=\dfrac{5}{6}\\ \dfrac{4}{9}=\dfrac{8}{18};\dfrac{1}{6}=\dfrac{3}{18}\\ 2,\\ \dfrac{5}{9}=\dfrac{10}{18};\dfrac{7}{8}=\dfrac{14}{16};\dfrac{24}{42}=\dfrac{12}{21}\)

1. \(\dfrac{3}{5}=\dfrac{21}{35};\dfrac{4}{7}=\dfrac{20}{35}\)

\(\dfrac{2}{3}=\dfrac{4}{6};\dfrac{5}{6}=\dfrac{5}{6}\)

\(\dfrac{4}{9}=\dfrac{16}{36};\dfrac{1}{6}=\dfrac{6}{36}\)

2. \(\dfrac{5}{9}=\dfrac{10}{18}\)

\(\dfrac{7}{8}=\dfrac{14}{16}\)

\(\dfrac{24}{42}=\dfrac{12}{21}\)

B

B

B

MSC:60 NHA BẠN 

ko bé ơi 

lớp tui có bạn cũng tên Nguyễn Trung Hiếu

a) $\frac{5}{3} = \frac{{5 \times 4}}{{3 \times 4}} = \frac{{20}}{{12}}$

Quy đồng mẫu số hai phân số $\frac{5}{3}$ và $\frac{{28}}{{12}}$ được $\frac{{20}}{{12}}$ và $\frac{{28}}{{12}}$

b) $\frac{2}{9} = \frac{{2 \times 9}}{{9 \times 9}} = \frac{{18}}{{81}}$

Quy đồng mẫu số hai phân số $\frac{2}{9}$ và $\frac{{17}}{{81}}$ được $\frac{{18}}{{81}}$ và $\frac{{17}}{{81}}$

c) $\frac{5}{8} = \frac{{5 \times 3}}{{8 \times 3}} = \frac{{15}}{{24}}$

Quy đồng mẫu số hai phân số $\frac{9}{{24}}$và $\frac{5}{8}$ được $\frac{9}{{24}}$và $\frac{{15}}{{24}}$

a) \(\dfrac{28}{12}=\dfrac{28:4}{12:4}=\dfrac{7}{3}\)

b) \(\dfrac{2}{9}=\dfrac{2\times9}{9\times9}=\dfrac{18}{81}\)

c) \(\dfrac{9}{24}=\dfrac{9:3}{24:3}=\dfrac{3}{8}\)

\(\frac{3}{15}\)= \(\frac{3:3}{15:3}\) = \(\frac{1}{5}\)

\(\frac{33}{44}\)= \(\frac{33:11}{44:11}\)= \(\frac{3}{4}\)

\(\frac{2}{8}\)= \(\frac{2:2}{8:2}\)= \(\frac{1}{4}\)

\(\frac{1}{5}\)= \(\frac{1\times4}{5\times4}\)= \(\frac{4}{20}\)

\(\frac{3}{4}\)=\(\frac{3\times5}{4\times5}\)= \(\frac{15}{20}\)

\(\frac{1}{4}\)= \(\frac{1\times5}{4\times5}\)= \(\frac{5}{20}\)

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

\(\frac{24}{36}\)=\(\frac{24:12}{36:12}\)= \(\frac{2}{3}\)

\(\frac{3}{8}\)= \(\frac{3:1}{8:1}\)= \(\frac{3}{8}\)

\(\frac{3}{4}\)=\(\frac{3\times6}{4\times6}\)= \(\frac{18}{24}\)

\(\frac{2}{3}\)=\(\frac{2\times8}{3\times8}\)=\(\frac{16}{24}\)

\(\frac{3}{8}\)= \(\frac{3\times3}{8\times3}\)=\(\frac{9}{24}\)

3/15= 1/5; 33/44=3/4; 2/8= 1/4

1/5= 1x 4/ 5x4= 4/20; 3/4= 3x 5/ 4x 5= 15/20; 1/4= 1x 5/ 4x 5= 5/20

9/12= 3/4; 24/36= 2/3; 3/8 không rút gọn được

3/4= 3x 6/ 4x6= 18/24; 2/3= 2x 8/ 3x 8= 16/24; 3/8= 3x 3/ 8x 3= 9/24

a, \(\frac{3}{15}=\frac{1}{5};\frac{33}{44}=\frac{3}{4};\frac{2}{8}=\frac{1}{4}\)

mcs:20

\(\frac{1}{5}=\frac{1x4}{5x4}=\frac{4}{20}:\frac{3}{4}=\frac{3x5}{4x5}=\frac{15}{20};\frac{1}{4}=\frac{1x5}{4x5}=\frac{5}{20}\)

b,\(\frac{9}{12}=\frac{3}{4};\frac{24}{36}=\frac{2}{3};\frac{3}{8}\)

msc:24

\(\frac{3}{4}=\frac{3x6}{4x6}=\frac{18}{24};\frac{2}{3}=\frac{2x8}{3x8}=\frac{16}{24};\frac{3}{8}=\frac{3x3}{8x3}=\frac{9}{34}\)