<PRE><B>Question 1033437</B>
let x = the old price.
then x + 2 = the new price.


25 * x + 20 * (x+2) = 3640


simplify to get 25 * x + 20 * x + 40 = 3640


combine like terms to get 45 * x + 40 = 3640


subtract 40 from both sides of the equation to get 45 * x = 3600


divide both sides of the equation by 45 to get x = 80.


the old price per liter is 80.
the new price per liter is 82.


25 * 80 + 20 * 82 = 3640.


old price per liter is 80 naira.



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