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

66 nha

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

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

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

\(\frac{10}{27}=\frac{1}{27}+\frac{5}{27}+\frac{4}{27}\)

\(\frac{13}{12}=\frac{1}{12}+\frac{7}{12}+\frac{5}{12}\)

\(\frac{15}{8}=\frac{7}{8}+\frac{5}{8}+\frac{3}{8}\)

cám ơn mọi người

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

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

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

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

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

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

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

7/2 = 1/2 + 3/1

13/27 = 1/9 + 10/27      

7/2 = 1/2 + 1/12

13/27 = 1/9 + 10/27

a,7/12=1/4+1/3