Răspuns:7x(21+16)=7x37=259
sau: =7x21+7x16=147+112=259
(136+13)x4=149x4=596
sau: =136x4+13x4=544+52=596
(130-18)x2=112x2=224
sau: =130x2-18x2=260-36=224
4x(425-350)=4x75=300
sau : 4x425-4x350=1700-1400=300
(34+16)x17=50x17=850
sau: 34x17+16x17=578+272=850
12x(52-25)=12x27=324
sau: 12x52-12x25=624-300=324
17x(94-39)=17x55=935
sau: 17x94-17x39=1598- 663=935
Explicație pas cu pas: