Răspuns:
a) I (35+5):5= 40:5= 8
II (35+5):5= (35:5)+(5:5)= 7+1= 8
b) I (35-25):5= 10:5= 2
II (35-25):5= (35:5)-(25:5)= 7-5= 2
c) I (36+24):6= 60:6= 10
II (36+24):6= (36:6)+(24:6)= 6+4= 10
d) I (18+30):6= 48:6= 8
II (18+30):6= (18:6)+(30:6)= 3+5= 8
e) I (28+35):7= 63:7= 9
II (28+35):7= (28:7)+(35:7)= 4+5= 9
f) I (49-21):7= 28:7= 4
II (49-21):7= (49:7)-(21:7)= 7-3= 4