Am I calculating this right?
 

I drive an automatic 1990 Toyota Camry LE with a 4 cylinder, 2L engine. When the gas tank is nearly empty and the fuel light is on, it takes about 50 litres to fill it up. This usually gets me about 600-620 kilometers. I calculated my gas mileage to be over 30 MPG! Is this correct?

nope, it's fairly innacurate because you're rounding but not terrible because you're using largest numbers you can. it doesn't matter where the gauge is as long as it's more than 100 miles (or so) use the trip odometer or write down the actual odometer reading AND write down the gallons you fill up (to at least one decimal place).

What happens when your low gas light burns out? lol I had a car like that once...had a place on the dash for it that you could see in the right light but I ran it dry once without it turning on. it's also fairly bad for the fuel pump

Hope these can help:):

https://www.fueleconomy.gov/mpg/MPG.do?action=calcMPG
https://www.oee.nrcan.gc.ca/transport...ator-input.cfm
https://www.sciencemadesimple.net/fuel_economy.php


IMHO, long term averages are more useful than numbers obtained from one tank.

I'll spring for this one, I love doing metric to standard calculations involving fuel mileage and liters / 100 kilometers to miles per gallon, don't ask I just do :p

The first step is to figure liters per 100 kilometers, I'll take an average of 610 kilometers (600-620) per 50 liters... To figure this, we need to take down 610 to 100 so 610 / 6.1 is the figure, hence dividing 50 / 6.1 = 8.1967 liters / 100 klm.

8.1967 liters per 100 klm.

Now we need a conversion calculator, hmmm...
First I found a chart which that does work,
looks like right around 29mpg.
I did find the actual mileage is 28.696 mpg
You could say 28.7, almost 29.

Formula used: 1 liters / 100 kilometers = 235.214584 miles per gallon
(so to figure this one I did 235.etc / 8.1967)

....................
Now just for kicks and because I'm in the mood, I'd like to compare this per weight to my own truck's 11 mpg...
The car you drive weighs about 3,000 pounds.
The truck I drive almost 8,000. So, 8 / 3...
hmmm... 8 / 3 = 2.667 x 11 mpg = 29.333 mpg pound per pound.
But now I'm wondering if I did THAT right :p

.................................
Here's the chart for a faster but slightly less accurate method:

Mpg - Litres Per 100 K
2.00 - 117.59
4.00 - 58.79
6.00 - 39.20
8.00 - 29.40
10.00 - 23.52
12.00 - 19.60
14.00 - 16.80
16.00 - 14.70
18.00 - 13.07
20.00 - 11.76
22.00 - 10.69
24.00 - 9.80
26.00 - 9.05
28.00 - 8.40
30.00 - 7.84
32.00 - 7.35
34.00 - 6.92
36.00 - 6.53
38.00 - 6.19
40.00 - 5.88

(620/1.61 Km/mile) / (50/4 L/G) = 30.8mpg pretty close!

Thanks for all of the help. My car has always gotten over 600 km per tank of gas, so I was just doing a rough estimate of what its fuel economy was like. In my oppinion, anything over 30mpg is pretty good for a '90 Camry with 260 000 km on it.

old 4-banger camry's don't get less than 30 hwy

My 86 (boxy, lighter, less powerful 2l single cam engine) that was about as aerodynamic as a cardboard box that was smashed between two cars because someone wasn't watching for stopped cars got 35-40 mpg carrying 500lbs going 80+ with the AC on.

Wow, that's pretty good.

it was a good little car. damage and looks included, I wish I hadn't sold it. it made a great get around town car