Răspuns :
Notez cu x-cantitatea de benzina din rezervor
x - (2/3*x+10)=70 l
1/3*x-10=70⇒ 1/3*x=80l⇒ x=3*80=240l
x - (2/3*x+10)=70 l
1/3*x-10=70⇒ 1/3*x=80l⇒ x=3*80=240l
a - (2/3a + 10) = 70 aducem la celasi numitor
3a - 2a - 30 = 210
a = 210 + 30
a = 240 litri
3a - 2a - 30 = 210
a = 210 + 30
a = 240 litri