a) \(\dfrac{2^4\cdot5^2\cdot7}{2^3\cdot5\cdot7^2\cdot11}=\dfrac{2^3\cdot5\cdot10\cdot7}{2^3\cdot5\cdot7\cdot77}=\dfrac{10}{77}\)

\(\dfrac{2^3\cdot3^3\cdot5^3\cdot7\cdot8}{3\cdot2^4\cdot5^3\cdot14}=\dfrac{2^3\cdot3\cdot5^3\cdot7\cdot3^2\cdot8}{3\cdot2^3\cdot2\cdot5^3\cdot14}=\dfrac{7\cdot3^2\cdot8}{2\cdot14}=\dfrac{63\cdot8}{2\cdot14}=18=\dfrac{1386}{77}\)

rút gọn rồi quy đồng nha

\(\frac{4^2.5.11}{44.20}=\frac{2^4.5.11}{2^2.11.2^2.5}=\frac{2^4.5.11}{2^4.5.11}=1\)

\(\frac{13.15.6}{18.65.7}=\frac{13.3.5.2.3}{2.3^2.13.5.7}=\frac{3^2.2.5.13}{2.3^2.13.5.7}=\frac{1}{7}\)

\(\frac{4^2.5.11}{44.20};\frac{13.15.6}{18.65.7};\frac{7.2.8.5^2}{14.2.5}\)và\(\frac{2^3.3^2.5}{3.2^3.5^3}\)

Ta có : \(\frac{4^2.5.11}{44.20}=\frac{42.5.11}{4.11.4.5}=\frac{4^2.1.1}{4^2.1.1}=1\)

\(\frac{13.15.6}{18.65.7}=\frac{13.3.5.6}{3.6.15.5.7}=\frac{1.1.1.1}{1.1.1.1.7}=\frac{1}{7}\)

\(\frac{7.2.8.5}{14.2.5}=\frac{7.2.2^3.5^2}{2.7.2.5}=\frac{1.1.2^2.5}{1.1.1.1}=\frac{20}{1}\)

\(\frac{2^3.3^3.5}{3.2^3.5^3}=\frac{1.3^2.1}{1.1.5^2}=\frac{9}{25}\)

+) Ta có : \(7=7\)

\(25=5^2\)

\(MC=BCNN\left(7;25\right)=5^2.7=175\)

Khi đó : ................

p/s : kham khảo

lưu ý : trả lời đầy đủ và đúng mới đc đúng

giúp mk vs, mai mình phải nộp rùi

C=1465030

\(\frac{1.2.5+3.4.15+4.8.20+7.14.350}{2.5.11+6.10.33+8.20.44+14.35.770}=\frac{1.2.5+1.3.2.2.3.5+1.2.2.8.4.5+1.7.7.2.70.5}{2.5.11+2.3.2.5.3.11+2.4.4.5.4.11+2.7.7.5.70.11}=\frac{1.2.5+1.2.5.18+1.2.5.64+1.2.5.3430}{2.5.11+2.5.11.18+2.5.11.64+2.5.11.3430}\)

\(=\frac{1.2.5.\left(1+18+64+3430\right)}{2.5.11.\left(1+18+64+3430\right)}=\frac{1}{11}\)