533)
1) В скобке: ( 16/76+86/76-75/76) = 27/76
4/9*19/6*27/76=1/2
5/9+1/2=10/18+9/18=19/18
2) (59/54-11/36)=(118/108-33/108)=(85/108)
85/108*18/5*16/7=136/21
136/21-(9/7*14/9)=136/21-2=94/21
534) 1) х=1/(2/3)=3/2
2) x=(1/6)/5=1/30
3) x=(1/4)/4=1/16
4) x=20/7