a) \(\dfrac{5}{6}-\dfrac{2}{14}\)

\(=\dfrac{5}{6}-\dfrac{1}{7}\)

\(=\dfrac{35}{42}-\dfrac{6}{42}\)

\(=\dfrac{29}{42}\)

b) \(\dfrac{5}{20}-\dfrac{1}{6}\)

\(=\dfrac{1}{4}-\dfrac{1}{6}\)

\(=\dfrac{3}{12}-\dfrac{2}{12}\)

\(=\dfrac{1}{12}\)

c) \(\dfrac{5}{9}-\dfrac{3}{12}\)

\(=\dfrac{5}{9}-\dfrac{1}{4}\)

\(=\dfrac{20}{36}-\dfrac{9}{36}\)

\(=\dfrac{11}{36}\)

d) \(8-\dfrac{4}{6}\)

\(=\dfrac{48}{6}-\dfrac{4}{6}\)

\(=\dfrac{44}{6}=\dfrac{22}{3}\).

Rút gọn rồi tính:                                                                                                                                               \(a.\frac{16}{24}-\frac{1}{3}=\frac{2}{3}-\frac{1}{3}=\frac{1}{3}\)

\(b.\frac{4}{5}-\frac{12}{60}=\frac{4}{5}-\frac{1}{5}=\frac{3}{5}\)

Tính rồi rút gọn:

\(a.\frac{17}{6}-\frac{2}{6}=\frac{15}{6}\)

\(b.\frac{16}{15}-\frac{11}{15}=\frac{5}{15}=\frac{1}{3}\)

\(c.\frac{19}{12}-\frac{13}{12}=\frac{6}{12}=\frac{1}{2}\)

1a2/3-1/3=1/3            c4/5-1/5=3/5             tinh roi rut gon 17/6-2/6=15/6=5/2             16/15-11/15=5/15=1/3           19/12-13/12=6/12=1/2

chuc bn hoc tot

lớp 1 à cu

A) \(\frac{7}{8}-\frac{5}{12}=\frac{84}{96}-\frac{40}{96}=\frac{44}{96}=\frac{11}{24}\)

B)\(\frac{8}{15}-\frac{2}{5}=\frac{8}{15}-\frac{6}{15}=\frac{2}{15}\)

C)\(\frac{5}{6}-\frac{3}{10}=\frac{50}{60}-\frac{18}{60}=\frac{32}{60}=\frac{8}{15}\)

D)\(\frac{7}{10}-\frac{1}{5}=\frac{7}{10}-\frac{2}{10}=\frac{5}{10}=\frac{1}{2}\)

2)A)\(\frac{5}{10}-\frac{2}{15}=\frac{1}{2}-\frac{2}{15}=\frac{15}{30}-\frac{4}{30}=\frac{11}{30}\)

B)\(\frac{5}{20}-\frac{1}{6}=\frac{1}{4}-\frac{1}{6}=\frac{6}{24}-\frac{4}{24}=\frac{2}{24}=\frac{1}{12}\)

C)\(\frac{6}{18}-\frac{6}{24}=\frac{1}{3}-\frac{1}{4}=\frac{4}{12}-\frac{3}{12}=\frac{1}{12}\)

D)\(\frac{5}{9}-\frac{3}{12}=\frac{5}{9}-\frac{1}{4}=\frac{20}{36}-\frac{9}{36}=\frac{11}{36}\)

Chúc bạn học tốt

12/18 + 12/42 = 2/3 + 2/7 = 14/21 + 6/21 = 20/21

1/2 + 2/4 + 3/6 + 4/8 + 5/10 + 6/12

= 1/2 + 1/2 + 1/2 + 1/2 + 1/2 + 1/2

= 1/2 x 6

=6/2

=3

Còn phần D thì sao😶

tra hieu gi ca

A) \(\dfrac{5}{10}-\dfrac{2}{15}\)

\(=\dfrac{1}{2}-\dfrac{2}{15}\)

\(=\dfrac{15}{30}-\dfrac{4}{30}\)

\(=\dfrac{11}{30}\)

B)\(\dfrac{5}{20}-\dfrac{1}{6}\)

\(=\dfrac{1}{4}-\dfrac{1}{6}\)

\(=\dfrac{6}{24}-\dfrac{4}{24}\)

\(=\dfrac{2}{24}=\dfrac{1}{12}\)

C) \(\dfrac{6}{18}-\dfrac{6}{24}\)

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

\(=\dfrac{4}{12}-\dfrac{3}{12}\)

\(=\dfrac{1}{12}\)

D) \(\dfrac{5}{9}-\dfrac{3}{12}\)

\(=\dfrac{5}{9}-\dfrac{1}{4}\)

\(=\dfrac{20}{36}-\dfrac{9}{36}\)

\(=\dfrac{11}{36}\).

a: =1/2-2/15

=15/30-4/30

=11/30

b: =1/4-1/6

=3/12-2/12

=1/12

c: =1/3-1/4

=1/12

d: =20/36-9/36

=11/36

1.

a, Ta có 28=14⇒14+56=1312(Bn tự quy đồng lên nhé !)

b,Ta có1216=34⇒18+34=78(Bn tự quy đồng lên nhé !)

c,Ta có636=16⇒14+16=512(Bn tự quy đồng lên nhé !)

d,Ta có1218=23⇒23+14=1112(Bn tự quy đồng lên nhé !)

7.Phần này mk chỉ cho đáp án thuia.67     ;     

 b,420=15     ;         

c,615       ;            

d,129

b: 12/20+6/18=3/5+1/3=9/15+5/15=14/15

c: 8/12+20/30=2/3+2/3=4/3

d: 10/12+12/36=5/6+2/6=7/6

Rút gọn rồi tính:

a) $\frac{16}{24}–\frac{1}{3}=\frac{2}{3}–\frac{1}{3}=\frac{2–1}{3}=\frac{1}{3}$     

b) $\frac{4}{5}–\frac{12}{60}=\frac{4}{5}–\frac{1}{5}=\frac{3}{5}$

Tính rồi rút gọn:

a) $\frac{17}{6}–\frac{2}{6}=\frac{17–2}{6}=\frac{15}{6}=\frac{5}{2}$             

b) $\frac{16}{15}–\frac{11}{15}=\frac{16–11}{15}=\frac{5}{15}=\frac{1}{3}$

c) $\frac{19}{12}–\frac{13}{12}=\frac{19–13}{12}=\frac{6}{12}=\frac{1}{2}$

a) \(\dfrac{21}{15}\) + \(\dfrac{2}{5}\) = \(\dfrac{9}{5}\)
b)  \(\dfrac{6}{16}\) + \(\dfrac{1}{8}\) = \(\dfrac{1}{2}\)

c)  \(\dfrac{3}{12}\) + \(\dfrac{3}{4}\) = 1

a, 2/8 + 5/6 = 1/4 +5/6 = 6/24 + 20/24 = 26/24 

b,1/8 + 12/16 = 1/8 + 3/4 = 4/32 + 24/32 = 28/32

c, 1/4 + 6/30 = 1/4 + 1/5 = 5/20 + 4/20 = 9/29

d, 12/18 + 12/42 = 2/3 + 2/7 = 14/21 + 6/21 = 20/21 

nhé

Bài 6 : rút gọn rồi tính

A ) 2/8 + 5/6 = 3/12 + 10/12 = 13/12.

B ) 1/8 + 12/16 = 1/8 + 6/8 = 7/8.

C ) 1/4 + 6/30 = 5/20+ 4/20 = 9/20.

D ) 12/18 + 12/42 = 14/21 + 6/21 = 20/21.