1. Calculam asa cum este.
2. Desfacem, inchidem parantezele.
a) 1.2*10+1.5*1.2=12+1.8=13.8
1.2*10+1.5*1.2=1.2*(10+1.5)=1.2*11.5=13.8
b) 2.7*(1.8+0.2)=2.7*2=5.4
2.7*(1.8+0.2)=2.7*1.8+2.7*0.2=5.4
c)0.4*0.5-0.4*0.25=0.4*(0.5-0.25)=0.4*0.25=0.1
0.4*0.5-0.4*0.25=0.2-0.1=0.1
d)(15,08-13,92)*0.42=1.16*0.42=0.4872
(15.08-13,92)*0.42=15.08*0.42-13.92*0.42=0.4872