10/27: 1/27+7/27+2/27

13/12: 1/12+7/12+5/12

15/8:7/8+3/8+5/8

10/27 = 1/27+2/27+7/27

13/12 = 1/12+5/12+7/12

15/8 =  3/8+5/8+7/8

ko biết nữa tui gà lắm

\(\dfrac{7}{12}=\dfrac{3}{12}+\dfrac{4}{12}=\dfrac{1}{4}+\dfrac{1}{3}\)

\(\dfrac{13}{27}=\dfrac{9}{27}+\dfrac{4}{27}=\dfrac{1}{3}+\dfrac{4}{27}\)

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

\(\dfrac{7}{12}\) = \(\dfrac{3+4}{12}\) = \(\dfrac{3}{12}\) + \(\dfrac{4}{12}\) = \(\dfrac{1}{4}\) + \(\dfrac{1}{3}\)

\(\dfrac{13}{27}\) = \(\dfrac{1+12}{27}\) = \(\dfrac{1}{27}\) + \(\dfrac{12}{27}\) = \(\dfrac{1}{27}\) + \(\dfrac{4}{9}\)

\(\dfrac{13}{27}\) = \(\dfrac{4+9}{27}\) = \(\dfrac{4}{27}\) + \(\dfrac{9}{27}\) = \(\dfrac{4}{27}\) + \(\dfrac{1}{3}\)

\(\dfrac{13}{27}\) = \(\dfrac{6+7}{27}\) = \(\dfrac{6}{27}\) + \(\dfrac{7}{27}\) = \(\dfrac{2}{9}\) +  \(\dfrac{7}{27}\)

a, \(\dfrac{7}{12}=\dfrac{6+1}{12}=\dfrac{6}{12}+\dfrac{1}{12}=\dfrac{6}{6\times2}+\dfrac{1}{12}=\dfrac{1}{2}+\dfrac{1}{12}\)

b, \(\dfrac{13}{27}=\dfrac{12+1}{27}=\dfrac{12}{27}+\dfrac{1}{27}=\dfrac{3\times4}{3\times9}+\dfrac{1}{27}=\dfrac{4}{9}+\dfrac{1}{27}\)

đây là đáp án của mình ạ.

66 nha

\(\frac{10}{27}=\frac{10x8}{27x8}=\frac{80}{216}\)

\(\frac{13}{12}=\frac{13x18}{12x18}=\frac{234}{216}\)

\(\frac{15}{8}=\frac{15x27}{8x27}=\frac{405}{216}\)

A. Gọi 5/12 = A/12 + B/12

Mà 5 = 1+4 => 5/12 = 1/12 + 4/12 

=> 5/12 = 1/12 + 1/3

B. 8/9 = 8x6/9x6 => 8/9 = 48/54

48/54 = 3/54 +18/54 + 27/54

=> 48/54= 1/18 + 1/3 + 1/2

Vì vậy 8/9 = 1/18 + 1/3 + 1/2

Dạ thầy cô hướng dẫn chị tiết giúp e với ạ?

C. 11/12 = 5/12 + 5/12 + 1/12

\(a,\dfrac{7}{15}=\dfrac{2}{15}+\dfrac{1}{3}\\ b,\dfrac{13}{27}=\dfrac{10}{27}+\dfrac{1}{9}\\ c,\dfrac{3}{18}=\dfrac{1}{18}+\dfrac{1}{9}\\ d,=\dfrac{1}{20}+\dfrac{1}{20}\)

Hi:D

7/12

=4/12+3/12

=1/4+1/3

5/6

=3/6+2/6

=1/3+1/2

5/6=1/2+1/3

7/12=1/3+1/4