This was a simple sign error, because it's cheaper to save fuel than to buy fuel, as is well known to companies that do it all the time -- for example, Dupont, SD micro electronics.
A fost o simplã greşeală de semn pentru cã este mai ieftin sã economiseşti combustibil decât sã cumperi, cum este bine ştiut de cãtre companiile care fac asta tot timpul -- de exemplu, Dupont, SD micro electronics.