a)1:(11/30-15/10)+(5/10)³:6/9=
1:(11-45)/30+125/1000x9/6=
1:(-34/30)+1/8x3/2=
-30/34+3/16=(-30x8+3x17)/272=
(-240+51)/272=-189/272≈-0,69
c))484/100x0,0009+3/4;[37/3X9/4-55/10X4]=
121/25x9/10000+3/4:(37/1x3/4-11/2x4)=
1089/250000+3/4:(111/4-22)=
1089/250000+3/4:(111-88)/4=
1089/250000+3/4:23/4=
1089/250000+3/4x4/23=
1089/250000+3/23=
(1089x23+3x250000)/5750000=
(25047+750000)/5750000=775047/5750000≈0,14
b)1/10:[(6/5+13/6)·(21/10+6/13)]:(14-1)/9=
1/10:[(36+65)/30·(21x13+6x10)/130]:15/9=
1/10:[101/30·333/130]:5/3=
1/10:(101/10·111/130)·3/5=
1/10:11211/1300·3/5=
1/10·1300/11211·3/5= simplif=
26/3737≈0,007