Question 762763
Regular gas = x
Premium gas = y
x + y = 340...1
2.25x + 2.85y = 819...2
Multiply (1) by 9
and (2) by 4
9x + 9y = 3060...3
9x + 11.4y = 3276...4
Subtract (3) from (4)
     2.4y = 216
        y = 90
Substitute y = 90 into (1)
x + y = 340
x + 90 = 340
     x = 340 - 90
     x = 250
Regular gas - 250 gallons
Premium gas - 90 gallons
Hope this helps.
:-)