Răspuns :
X + 6 x 7 = 100
X+42=100
X=100-42
X=58
9•10-x=15
90-x=15
x=15-90
X=75
27•37-X=599
999-x=599
X=599-999
X=400
Coroana?
X+42=100
X=100-42
X=58
9•10-x=15
90-x=15
x=15-90
X=75
27•37-X=599
999-x=599
X=599-999
X=400
Coroana?