\(\frac{243^5.81^7.9^{15}.3^6.9^4.3^{18}}{9^8.729^8.81^9.27^5}=\frac{\left(3^5\right)^5.\left(3^4\right)^7.\left(3^2\right)^{15}.3^6.\left(3^2\right)^4.3^{18}}{\left(3^2\right)^8.\left(3^6\right)^8.\left(3^4\right)^9.\left(3^3\right)^5}=\frac{3^{25}.3^{28}.3^{30}.3^6.3^8.3^{18}}{3^{16}.3^{48}.3^{36}.3^{15}}=\frac{3^{115}}{3^{115}}=1\)

\(=\dfrac{5\cdot2^{12}\cdot3^8-3^9\cdot2^{12}}{2^{15}\cdot3^{18}-2^{13}\cdot3^9}\)

\(=\dfrac{2^{12}\cdot3^8\left(5-3\right)}{2^{13}\cdot3^9\left(2^2\cdot3^9-1\right)}\)

\(=\dfrac{1}{3\cdot\left(4\cdot3^9-1\right)}\)

a) \(110 – 7^2 + 22:2\) = \(110 – 49 + 11 = 61 + 11 = 72\)

b) \(9.(8^2 – 15)= 9.(64 – 15 ) = 9.49 = 441\)

c) \(5.8 – (17 + 8):5 = 40 – 25:5 = 40 – 5 = 35\)

d) \( 75:3 + 6.9^2= 25 + 6.81 = 25 + 486 = 511\)

Điểm 10 : 25%

Điểm 9 : 25+ 6,25 = 31,25%

18 bạn điểm 8 hoặc 9

giả sử điểm 10 gồm 18 bạn tương ứng 25%

Vậy số bạn là : 18 x 100 : 25 = 72 bạn

giả sử điểm 9 gồm 18 bạn tương ứng 31,25%

Vậy số bạn là : 18 x 100 : 31,25 = 57,6 bạn (vô lí )

ĐÁp số 72 bạn

kho v~

kết bạn chị chị chỉ cho chứ chị ko bt  kết bạn trên olm nha ém

a: \(\frac{\left(-5\right)^{60}\cdot30^5}{15^5\cdot5^{61}}\)

\(=\frac{5^{60}}{5^{61}}\cdot\left(\frac{30}{15}\right)^5\)

\(=\frac{2^5}{5}=\frac{32}{5}\)

b: \(\frac{\left(-3\right)^{10}\cdot15^5}{25^3\cdot\left(-9\right)^7}=\frac{3^{10}\cdot3^5\cdot5^5}{5^6\cdot\left(-1\right)\cdot3^{14}}=\frac{-3^{15}}{3^{14}}\cdot\frac15=-\frac35\)

c: \(4^6\cdot9^5+6^9\cdot120\)

\(=2^{12}\cdot3^{10}+2^9\cdot3^9\cdot2^3\cdot3\cdot5\)

\(=2^{12}\cdot3^{10}+2^{12}\cdot3^{10}\cdot5=2^{12}\cdot3^{10}\cdot6=2^{13}\cdot3^{11}\)

\(8^4\cdot3^{12}-6^{11}\)

\(=2^{12}\cdot3^{12}-2^{11}\cdot3^{11}\)

\(=2^{11}\cdot3^{11}\left(2\cdot3-1\right)=2^{11}\cdot3^{11}\cdot5\)

Ta có: \(\frac{4^6\cdot9^5+6^9\cdot120}{8^4\cdot3^{12}-6^{11}}\)

\(=\frac{2^{13}\cdot3^{11}}{2^{11}\cdot3^{11}\cdot5}=\frac{2^2}{5}=\frac45\)

d: \(4^2\cdot25^2+32\cdot125\)

\(=2^4\cdot5^4+2^5\cdot5^3\)

\(=2^4\cdot5^3\left(5+2\right)=2^4\cdot5^3\cdot7\)

\(\frac{4^2\cdot25^2+32\cdot125}{2^3\cdot5^2}\)

\(=\frac{2^4\cdot5^3\cdot7}{2^3\cdot5^2}=2\cdot5\cdot7=10\cdot7=70\)