1. 24*156+24-31-7*50=24*(156+1)-31-7*50=24*157-31-350=
24*157=3768
=3768-31-350=3737-350= 3387
2. 14*12-14*7-5*13=14*(12-7)-5*13=14*5-5*13=
14*5= 70
5*13=65
=70-65=5
3. 14*12-14*7-5*13=14*(12-7)-5*13=14*5-5*13=
14*5= 70
5*13=65
=70-65=5
4. 32*25+32*11-36*30=32*(25+11)-36*30=32*36-36*30=36*(32-30)=36*2=72
5. 177-36-177*31-77*55=177*(1-31)-36+77*55=
77*55=4235
=177* (-30)-36+4235=
177* (-30)= - 5310
=- 5310-36+4235= - 1111
PS: punctul 2 este identic cu 3
