a) \(\dfrac{2727-101}{3.303+404}=\dfrac{2626}{909+404}=\dfrac{2626}{1313}=2\)

b) \(\dfrac{8.9-4.15}{12.7-180}=\dfrac{72-60}{84-180}=\dfrac{12}{-96}=\dfrac{-1}{8}\)

c) \(\dfrac{-19}{3^2.7.11}=\dfrac{-19}{9.7.11}=\dfrac{-19}{63.11}=\dfrac{-19}{693}\)

d) \(\dfrac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}=\dfrac{2^{12}.3^{10}+120.6^9}{2^{12}.3^{12}-6^{11}}=\dfrac{2^2.6^{10}+20.6.6^9}{6^{12}-6^{11}}=\dfrac{4.6^{10}+20.6^{10}}{6^{11}\left(6-1\right)}=\dfrac{\left(4+20\right).6^{10}}{5.6^{11}}=\dfrac{24}{30}=\dfrac{4}{5}\)

\(a,\frac{5\cdot6+5\cdot7}{5\cdot8+20}=\frac{\left(5\cdot6+5\cdot7\right)\div2}{\left(5.8+20\right)\div2}=\frac{13}{12}\)

\(\frac{8.9-4.15}{12.7-180}=\frac{12.6-12.5}{12.7-12.15}=\frac{1}{-8}=\frac{-1}{8}\)

\(Ta\)\(co\)\(\frac{13}{12}=\frac{13.2}{12.2}=\frac{26}{24}\)

\(\frac{-1}{8}=\frac{3\left(-1\right)}{3.8}=\frac{-3}{24}\)

Phần b bạn tính ra rồi làm tương tự phần a nha chúc bạn học giỏi!!!

\(\frac{thank}{you}\)

\(a,\dfrac{-5}{8};\dfrac{7}{10};\dfrac{16}{19};\dfrac{20}{23}\)

\(\Rightarrow\dfrac{20}{23}>\dfrac{16}{19}>\dfrac{7}{10}>\dfrac{-5}{8}\)

Vậy \(\dfrac{20}{23}>\dfrac{16}{19}>\dfrac{7}{10}>\dfrac{-5}{8}\)

\(b,\dfrac{5\times6+6\times7}{5\times5+20}\)và \(\dfrac{8\times9-4\times15}{12\times7-180}\)

Xét : \(\dfrac{5\times6+6\times7}{5\times5+20}\)

\(=\dfrac{\left(5+7\right)\times6}{5\times5+5\times4}\)

\(=\dfrac{12\times6}{\left(5+4\right)\times5}\)

\(=\dfrac{72}{9\times5}\)

\(=\dfrac{72}{45}\)

\(=\dfrac{8}{5}\)

Xét : \(\dfrac{8\times9-4\times15}{12\times7-180}\)

\(=\dfrac{72-60}{84-180}\)

\(=\dfrac{12}{-96}\)

\(=\dfrac{-1}{8}\)

Quy đồng \(\dfrac{8}{5}=\dfrac{8\times8}{5\times8}=\dfrac{64}{40}\\ \dfrac{-1}{8}=\dfrac{\left(-1\right)\times5}{8\times5}=\dfrac{-5}{40}\)

Vì \(\dfrac{64}{40}>\dfrac{-5}{40}\)

\(\Rightarrow\dfrac{8}{5}>\dfrac{-1}{8}\)

\(\Rightarrow\dfrac{5\times6+6\times7}{5\times5+20}>\dfrac{8\times9-4\times15}{12\times7-180}\)

Vậy \(\dfrac{5\times6+6\times7}{5\times5+20}>\dfrac{8\times9-4\times15}{12\times7-180}\)

đề bài là gì ?? so sánh hay là tính 

\(\frac{5.6+5.7}{5.8+20}\)và \(\frac{8.9-4.15}{12.7-180}\)

Ta có : \(\frac{5.6+5.7}{5.8+20}=\frac{30+35}{40+20}=\frac{65}{60}=\frac{13}{12}\)

\(\frac{8.9-4.15}{12.7-180}=\frac{72-60}{84-180}=\frac{12}{-96}=\frac{-1}{8}\)

+) Tìm \(12=2^2.3\)

\(8=2^3\)

\(MC=BCNN\left(12,18\right)=2^3.3=24\)

Khi đó : \(\frac{13}{12}=\frac{13.2}{12.2}=\frac{26}{24}\)

\(\frac{-1}{8}=\frac{-1.3}{8.3}=\frac{-3}{24}\)

p/s : kham khảo

= \(\frac{65}{60}\)và  \(\frac{12}{-96}\)

\(\Rightarrow65.\left(-96\right)=\)là một số âm

\(\Rightarrow12.60=\)là một số dương

\(\Rightarrow\)đường lớn hơn âm

\(\Rightarrow\)5.6 + 5.7/5.8 + 20 < 8.9 - 4.15/12.7 - 180

Ta có: \(\frac{2^5.7+2^5}{2^5.5^2-2^5.3}\) = \(\frac{2^5.\left(7+1\right)}{2^5.\left(5^2-3\right)}\) = \(\frac{2^5.8}{2^5.22}\) = \(\frac{8}{22}\) =\(\frac{56}{154}\)

​\(\frac{3^4.5-3^6}{3^4.13+3^4}\) = \(\frac{3^4.\left(5-3^2\right)}{3^4.\left(13+1\right)}\) = \(\frac{3^4.\left(-4\right)}{3^4.14}\) = \(\frac{-4}{14}\)= \(\frac{-44}{154}\)

Ta có: \(\frac{8.9-4.15}{12.7-180}\)=\(\frac{4.2.3.3-4.3.5}{12.7-12.15}\)=\(\frac{4.3\left(2.3-5\right)}{12.\left(7-15\right)}=\frac{1}{-8}=\frac{-1}{8}\)

tA CÓ :

\(\frac{5.6+5.7}{5.8+20}=\frac{5\left(6+7\right)}{5.\left(8+4\right)}=\frac{5.13}{5.12}=\frac{13}{12}\)

\(\frac{8.9-4.15}{12.7-180}=\frac{3.4\left(2.3-5\right)}{12\left(7-15\right)}=\frac{12\left(6-5\right)}{12\left(7-15\right)}=\frac{6-5}{7-15}=\frac{1}{-8}\)

giúp mik vs mik cần gấp 

VIẾT HẲN PS RA CHỨ KO HIỂU

5*6+5*7/5*8+20=5*6+5*7/5*8+5*4=6+7/8+4=13/12

4*15/12*7-186=1*15/3*7-186=15/-165=1/-11

quy đồng

13/12=143/-132

1/-11=12/-132

cho mik nha