<PRE><B>Question 726833</B>
Premium gas sells at 62 cents/L.
 Regular gas sells at 59.5 cents/L.
 To boost sales, a middle octane gas is formed by mixing premium and regular.
 If 1000 L of this middle octane gas is produced and sold at 60.5 cents/L, how much of each type of gasoline was used? 
:
Let x = amt of 62 cent gas used
the total is to be 1000L, therefore
(1000-x) = amt of 59.5 cent gas
:
A typical mixture equation
62x + 59.5(1000-x) = 60.5(1000)
62x + 59500 - 59.5x = 60500
62x - 59.5x = 60500 - 59500
2.5x = 1000
x = 1000/2.5
x = 400L of the 62 cent gas
then
1000-400 = 600L of the 59.5 cent gas
:
:
Check this
62(400) + 59.5(600) = 60.5(1000)
24800 + 35.700 = 60500 </PRE>