log25(32)*log27(625)*log128(81)=

log5^2(2^5)*log3^3(5^4)*log2^7(3^4)=

5/2*log5(2)*4/3*log3(5)*4/7*log2(3)=

5*log5(2)*2/3*log3(5)*4/7*log2(3)=

5*log3(2)/log3(5)*2/3*log3(5)*4/7*log2(3)=

5*log3(2)*2/3*4/7*log2(3)=

5*2/3*4/7=40/21

Ответ: 40/21= 1*19/21