Giúp mình nhanh nha

a: \(\frac79-\frac{4}{15}+\frac61\)

\(=\frac{35}{45}-\frac{12}{45}+6\)

\(=6+\frac{23}{45}=\frac{270}{45}+\frac{23}{45}=\frac{293}{45}\)

b: \(\frac{44}{21}-\left(\frac34+\frac{2}{21}\right)\)

\(=\frac{44}{21}-\frac{2}{21}-\frac34\)

\(=2-\frac34=\frac54\)

c: \(\frac{17}{12}+\frac{13}{7}-\frac67+\frac{7}{12}\)

\(=\frac{17}{12}+\frac{7}{12}+\left(\frac{13}{7}-\frac67\right)\)

=2+1

=3

17/20, 16/3, 23/63, 17/2, 5/14

17/20, 16/3, 23/63, -17/2, 5/14

\(\frac{6}{9}+\left(\frac{24}{15}:\frac{12}{9}:\frac{6}{15}\right)\)

\(=\frac{2}{3}+\left(\frac{24}{15}.\frac{9}{12}.\frac{15}{6}\right)\)

\(=\frac{2}{3}+\frac{24.9.15}{15.12.6}\)

\(=\frac{2}{3}+\frac{2.3.1}{1.1.2}\)

\(=\frac{2}{3}+3\)

\(=\frac{2}{3}+\frac{9}{3}\)

\(=\frac{11}{3}\)

Chúc bạn học tốt !!! 

1.x=107/9

k cho mình nha

giải hẳn ra nha

\(12+9\frac{6}{12}\)

\(=12+9\frac{1}{2}\)

\(=12+9+\frac{1}{2}\)

\(=21+\frac{1}{2}\)

\(=21\frac{1}{2}\)

\(12+9\frac{6}{12}\)

\(=12+\frac{114}{12}\)

\(=12+9,5\)

\(=21,5\)

Vậy \(12+9\frac{6}{12}=21,5\)

8/9 = 8x3/9x3=24/27

12/13 = 12x2/13x2=24/26

Vậy 24/26 > 24/27

12/36 = 12x5/35x5 = 60/175

15/60=15x4/60x4 = 60/240

60/175 > 60/240 nên 12/36 > 15/60

\(a.\frac{8}{9}và\frac{12}{13}\)

\(\frac{8}{9}=\frac{8\times3}{9\times3}=\frac{24}{27}vả\frac{12}{13}=\frac{12\times2}{13\times2}=\frac{24}{26}\)

\(Vì\frac{24}{27}< \frac{24}{26}nên\frac{8}{9}< \frac{12}{13}\)

\(b.\frac{12}{36}và\frac{15}{60}\)

\(\frac{12}{36}=\frac{12\div4}{36\div4}=\frac{3}{9}và\frac{15}{60}=\frac{15\div5}{60\div5}=\frac{3}{12}\)

\(Vì\frac{3}{9}>\frac{3}{12}nên\frac{12}{36}>\frac{15}{60}\)

khó thấy quá bạn ơi

a) \(\frac{2}{5}+\left(\frac{2}{8}+\frac{3}{5}+\frac{6}{8}\right)=\left(\frac{2}{5}+\frac{3}{5}\right)+\left(\frac{2}{8}+\frac{6}{8}\right)=1+1=2\)

b) \(\frac{6}{9}+\left(\frac{15}{25}+\frac{12}{9}+\frac{6}{15}\right)=\left(\frac{6}{9}+\frac{12}{9}\right)+\left(\frac{15}{25}+\frac{6}{15}\right)\)

\(=2+\left(\frac{3}{5}+\frac{2}{5}\right)=2+1=3\)