Question

реши рациогально: (170+30)×2; (140+20)÷20;400÷(5×20); (275+15)÷5; 84÷(2+4); 25×(4+50); (50×70)×4; (35×12)×2

Answer 1

(170+30)×2=200×2=400
140+(20÷20)=140+1=141
400÷(5×20)=400÷100=4
275+(15÷5)=275+3=278
(84÷2)+4=42+4=46
(25×4)+50=100+50=150
(50×4)×70=200×70=14000
(35×2)×12=70×12=840