a) 1/2

b) 3/8

~~~~~~~~~hok tốt~~~~~~~~~~~~

A/ \(\frac{1}{2}\)

B/ \(\frac{3}{8}\)  

a) 3/5:3/4=3/5x4/3=(3x4)/(5x3)=12/15=4/5

b)2/5:3/10=2/5x10/3=(2x10)/(5x3)=20/15=4/3

c)9/8:3/4=9/8x4/3=(9x4)/(8x3)=36/32=9/8

d)1/4:1/2=1/4x2=2/4=1/2

e)1/8:1/6=1/8x6=6/8=3/4

g)1/5:1/10=1/5x10=10/5=2

a) 3/5 : 3/4 = 4/5

b) 2/5 : 3/10 = 4/3

c) 9/8 : 3/4 = 3/2

d)  1/4 : 1/2 = 1/2

e) 1/8 : 1/6 = 3/4

g) 1/5 : 1/10 = 2

tk tớ nha

a)3/5:3/4=3/5x4/3=12/15=4/5

b)2/5:3/10=2/5x10/3=20/15=5/3

c)9/8:3/4=9/8x4/3=36/24=3/2

d)1/4:1/2=1/4x2=1/2

e)1/8:1/6=1/8x6=3/4

g)1/5:1/10=1/5x10=2

a) 2/5 + 1/2 + 7/10

= 4/10 + 5/10 + 7/10

= 9/10 + 7/10

= 16/10 = 8/5

b) 4/9 + 11/8 - 5/6

= 32/72 + 99/72 - 60/72

= 191/72

c) 9/20 - 8/15 x 5/12

= 9/20 - 2/9

= 41/180

d) 2/3 : 4/5 : 7/12

= 5/6 : 7/12

= 10/7

a,2/5+1/2+7/10

=4/10+5/10+7/10

=16/10

=8/5

b,4/9+11/8-5/6

=32/72+99/72-5/6

=131/72-5/6

=131/72-60/72

=71/72

c,9/20-8/15x5/12

=9/20-2/9

=41/180

d,2/3:4/5:7/12

=2/5x5/4x12/7

=6/7

Bài 2:

a: 2/6x5/3=10/18=5/9

b: 11/9x5/10=55/90=11/18

c: 3/9x6/8=1/3x3/4=1/4

d: 4/9x12/16=48/144=1/3

e: 25/15x6/7=5/3x6/7=30/21=10/7

f: 6/10x15/20=90/200=9/20

Bài 1

4/5 x 6/7= 24/35

2/9 x 1/2= 2/18= 1/9

1/2 x 8/3= 8/6= 4/3

7/9 x 6/5= 42/45= 14/15

8/7 x 5/9= 40/63

10/11 x 22/15= 220/165= 4/3

Bài 2

2/6 x 5/3= 1/3 x 5/3=5/9

11/9 x 5/10= 11/9 x 1/2= 11/18

3/9 x 6/8= 1/3 x 3/4 =3/12= 1/4

4/9 x 12/16= 4/9 x 3/4= 12/36= 1/3

25/15 x 6/7= 5/3 x 6/7= 30/21= 10/7

6/10 x 15/20= 3/5 x 3/4= 9/20

bài 1

4/5 x 6/7 = 24/35

2/9 x 1/2 = 1/9

1/2 x 8/3 = 4/3

7/9 x 6/5 = 14/15

8/7 x 5/9 = 14/15

8/7 x 5/9 = 40/63

10/11 x 22/15 = 4/3

dễ thế mà cũng ko bik chia phan so = nhan đảo ngược

A. \(\frac{2}{5}\div\frac{2}{3}=\frac{2}{5}\times\frac{3}{2}=\frac{2\times3}{5\times2}=\frac{3}{5}\text{ }\)

B. \(\frac{4}{7}\div\frac{4}{5}=\frac{4}{7}\times\frac{5}{4}=\frac{4\times5}{7\times4}=\frac{5}{7}\)

C. \(\frac{1}{6}\div\frac{1}{3}=\frac{1}{6}\times\frac{3}{1}=\frac{3}{6}=\frac{1}{2}\)

D. \(\frac{1}{4}\div\frac{1}{8}=\frac{1}{4}\times\frac{8}{1}=\frac{8}{4}=2\)

a, 13/6+5/8 : -3/4 - 7/12.4

= 13/6 + -5/6-7/3

=8/6-7/3

= -6/6

= -1

b, ( 73/5 - 21/3) + ( 4/3-43/5 )

= 73/5-21/3+4/3-43/5

=( 73/5-43/5)-(21/3-4/3)

= 6-17/3

=1/3

c, 7/5.4/9 +7/5: 9/16- 14/10.2/9

= 7/5.4/9 +7/5.16/9 - 14/45

=7/5.(4/9+16/9)-14/45

=7/5.20/9-14/45

= 140/45 - 14/45

= 126/45

Xong rùi nè! Nhưng bạn kiểm tra lại giùm nhé vì làm vào ban đêm nên hơi bất tiện

Trời ạ. 7 3/5 chứ k phải 73/5 -_-

ghi rõ thêm từ và nhé!

a: \(\dfrac{1}{8}+\dfrac{5}{8}=\dfrac{1+5}{8}=\dfrac{6}{8}=\dfrac{3}{4}\)

b: \(\dfrac{1}{15}+\dfrac{4}{15}=\dfrac{1+4}{15}=\dfrac{5}{15}=\dfrac{1}{3}\)

c: \(\dfrac{5}{9}+\dfrac{7}{9}=\dfrac{5+7}{9}=\dfrac{12}{9}=\dfrac{4}{3}\)

d: \(\dfrac{23}{100}+\dfrac{27}{100}=\dfrac{23+27}{100}=\dfrac{50}{100}=\dfrac{1}{2}\)

a) 18+58=1+58=68=3418+58=1+58=68=34

b) 115+415=1+415=515=13115+415=1+415=515=13

c) 59+79=5+79=129=4359+79=5+79=129=43

d) 23100+27100=23+27100=50100=12

\(A=\frac{3}{4}.\frac{8}{9}.\frac{15}{16}.....\frac{9999}{10000}\)

\(=\frac{1.3}{2.2}.\frac{2.4}{3.3}.\frac{3.5}{4.4}......\frac{99.101}{100.100}\)

\(=\frac{1.2.3...99}{2.3.4....100}.\frac{3.4.5....101}{2.3.4....100}\)

\(=\frac{1}{100}.\frac{101}{2}\)

\(=\frac{101}{200}\)