Explicație pas cu pas:
27)
a)(3x103)+(3x114)+(3x108)=309+342+324=975
b)3x(103+114+108)=3x325=975
28)
278x2=556(baloane galbene)
278+556=834(baloane albastre)
3x(278+556+834)=3x1668=5004 lei
29)
3x(124+198)=2x(183+300)
3x322=2x483
966=966. adevărat
2x(268+147)=3x(104+195)
2x415=3x299
830=897 fals
6x(59+78)=7x(29+112)
6x137=7x141
822=987. fals
4x(109+125)=2x(199+269)
4x234=2x468
936=936. adevărat
