\(\frac{28}{35}\times\frac{15}{72}\times1\frac{7}{49}=\frac{4}{5}\times\frac{5}{24}\times\frac{8}{7}=\frac{160}{840}=\frac{4}{21}\)

\(\dfrac{15}{35}+\dfrac{7}{10}=\dfrac{3}{7}+\dfrac{7}{10}=\dfrac{30}{70}+\dfrac{49}{70}=\dfrac{79}{70}\)

\(\dfrac{27}{72}+\dfrac{11}{24}=\dfrac{3}{8}+\dfrac{11}{24}=\dfrac{9}{24}+\dfrac{11}{24}=\dfrac{20}{24}=\dfrac{5}{6}\)

\(\dfrac{6}{12}+\dfrac{7}{6}=\dfrac{1}{2}+\dfrac{7}{6}=\dfrac{3}{6}+\dfrac{7}{6}=\dfrac{10}{6}=\dfrac{5}{3}\)

a: 78/42-4/7=13/7-4/7=9/7

100/110-56/88=10/11-7/11=3/11

75/35-11/7+21/49=15/7-11/7+3/7=7/7=1

99/72-15/40-1212/1616=11/8-3/8-3/4=1-3/4=1/4

`2/5 + 9/15= 2/5 + 3/5=5/5=1`

`15/45 + 25/30= 1/3 + 5/6= 2/6+5/6=7/6`

`28/32 + 45/72=7/8+ 5/8=12/8=3/2`

`8/28 + 5/30= 2/7 + 1/6= 12/42 + 7/42= 19/42`

=4/5 . 5/24 . 16/9

= 1/6 . 16.9 

=8/27

Đúng thì tk nha

Ai tk kb luôn

28/35x15/72x1và7/9=4/5x5/24x16/9=20/100x16/9=320/900=16/45

mình làm vậy đúng ko?

28/35 rút gọn được 4/5. 15/72 là phân số tối giản rồi.  1 và 7/9 đổi ra phân số đc 16/9, 16/9 cũng là phân số tối giản rồi

4/5 x 15/72 = 100/360 

100/360 x 16/9 = 1600/ 3240

\(\dfrac{4}{5}+\dfrac{1}{4}=\dfrac{21}{20}\)

=4/5+1/4=21/20

\(\dfrac{4}{5}+\dfrac{1}{4}=\dfrac{21}{20}\)

a)25/50 + 5/15 = 1/2 + 1/3 = 5/6

b)72/90 + 7/28 = 4/5 + 1/4 =\(1\frac{1}{20}\)

c)32/96 + 8/28 = 1/3 + 2/7 = 13/21

Chúc bạn tết vui vẻ nha!

Cảm ơn bạn

a ) \(\frac{25}{50}+\frac{5}{15}=\frac{1}{2}+\frac{1}{3}=\frac{5}{6}\)

b ) \(\frac{72}{90}+\frac{7}{28}=\frac{4}{5}+\frac{1}{4}=\frac{21}{20}\)

c ) \(\frac{32}{96}+\frac{8}{28}=\frac{1}{3}+\frac{2}{7}=\frac{13}{21}\)

Chúc bạn học tốt !

\(\frac{25}{50}+\frac{5}{15}=\frac{1}{2}+\frac{1}{3}=\frac{3}{6}+\frac{2}{6}=\frac{5}{6}\)

\(\frac{72}{90}+\frac{7}{28}=\frac{8}{10}+\frac{1}{4}=\frac{32}{40}+\frac{10}{40}=\frac{42}{40}=\frac{21}{20}\)

\(\frac{32}{96}+\frac{8}{28}=\frac{1}{3}+\frac{2}{7}=\frac{7}{21}+\frac{6}{21}=\frac{13}{21}\)

1/2 + 1/3

1/2=1.3/2.3=3/6 : 1/3=1.2/3.2=2/6

3/6 + 2/6=5/6