Question

13.Calculati :
a) [-0,05+18 supra 19 x (5 supra 12 - 0,3(6)-0,1(5))] : (-0,025) 
P.S REZOLVAREA COMPLETA
                 

Answer 1

0,05=5/100=1/20
0,3(6)=36-3/90=33/90=11/30
0,1(5)=15-1/90=14/90=7/45
0,025=25/1000=1/40
[-1/20+18/19x(5/12-11/30-7/45)]:1/40=
[-1/20+18/19x(5x15-11x6-7x4)/180]x40=
[-1/20+18/19x(75-66-28)/180]x40
=[-1/20+18/19x(9-28)/180]x40=
[-1/20+18/19x(-19/180)]x4=
[-1/20-1/10]x40=
[(-1-2)/20]x40=
-3x2=-6