phân số thứ nhất =16/11

phân số thứ hai = -5/9

phân số thứ ba = 10/77

a: \(\dfrac{4\cdot5+4\cdot11}{8\cdot7+4\cdot3}=\dfrac{20+44}{56+12}=\dfrac{64}{68}=\dfrac{16}{17}=\dfrac{11088}{11781}\)

\(\dfrac{-15\cdot8+10\cdot7}{5\cdot6+20\cdot3}=\dfrac{-120+70}{30+60}=\dfrac{-50}{90}=\dfrac{-5}{9}=\dfrac{-6545}{11781}\)

\(\dfrac{2^4\cdot5^2\cdot7}{2^3\cdot5\cdot7^2\cdot11}=\dfrac{2\cdot5}{7\cdot11}=\dfrac{10}{77}=\dfrac{1530}{11781}\)

A=\(\dfrac{4.5+4.11}{8.7-4.3}=\dfrac{4.\left(5+11\right)}{56-12}=\dfrac{4.16}{44}\dfrac{1.16}{11}=\dfrac{16}{11}\)

Câu B chỉ cần phân tích số 6 và 20 ở dưới mẫu thành 6=3.2, 20=4.5 rồi bn cứ thế mà tiếp tục!

Câu 1: 

\(\dfrac{14\cdot34-21\cdot10}{28\cdot10-28\cdot16}=\dfrac{7\cdot2\cdot34-7\cdot3\cdot10}{28\left(10-16\right)}\)

\(=\dfrac{7\left(2\cdot34-3\cdot10\right)}{28\cdot\left(-6\right)}=\dfrac{1}{4}\cdot\dfrac{68-30}{-6}=\dfrac{1}{4}\cdot\dfrac{38}{-6}=\dfrac{38}{-24}=-\dfrac{19}{12}\)

\(-\frac{20+44}{56-12}=\frac{-64}{44}=\)\(\frac{-16}{11}\)

\(\frac{-120+70}{30+60}\)=\(\frac{-5}{9}\)

Ta có \(\frac{-16}{11}< \frac{-11}{11}=-1\)

\(\frac{-5}{9}>\frac{-9}{9}=-1\)

nên \(\frac{-5}{9}>-1>\frac{-16}{11}\)

Vậy \(\frac{-5}{9}>\frac{-16}{11}\)

tự kết luận nhé

\(\text{Ta có :}\)\(-\frac{4.5+4.11}{8.7-4.3}=\frac{-4\left(5+11\right)}{4\left(2.7-3\right)}=\frac{-16}{24}=\frac{-4}{6}\)

\(\frac{-15.8+10.7}{5.6+20.3}=\frac{-5\left(3.8-2.7\right)}{5.\left(6+2.3\right)}=\frac{-10}{12}=\frac{-5}{6}\)

\(\text{Vì:}\)\(-\frac{4}{6}>\frac{-5}{6}\left(-4>-5\right)\)

\(\text{Nên :}\)\(-\frac{4.5+4.11}{8.7-4.3}>\)\(\frac{-15.8+10.7}{5.6+20.3}\)

\(-\frac{4.5+4.11}{8.7-4.3}=-\frac{4.\left(5+11\right)}{4.\left(14-3\right)}=-\frac{4.16}{4.11}=\frac{-16}{11}\)

\(\frac{-15.8+10.7}{5.6+20.3}=\frac{\left(-5\right).3.8+5.2.7}{5.2.3+2.2.5.3}=\frac{5.\left(-3.8+2.7\right)}{5.2.3.\left(1+2\right)}\)

\(=\frac{5.\left(-10\right)}{5.2.3.3}=\frac{-5}{9}\)

\(\frac{-5}{9}>\frac{-16}{11}\)