Răspuns :
(x+20)÷12+68=78
(x+20):12=78-68
(x+20):12=10
(x+20)=12x20
(x+20)=120
x=120-20=100
x=100
(x+20):12=78-68
(x+20):12=10
(x+20)=12x20
(x+20)=120
x=120-20=100
x=100
(x+20):12+68=78
=(x+20):12=10
X=12•20
(x+20)=120
X=120-20=100
X=100
=(x+20):12=10
X=12•20
(x+20)=120
X=120-20=100
X=100