As the cost of gas goes up it becomes more and more important to use it more efficiently and therefore people become more interested in how much it is costing to drive a mile. It is relatively easy to calculate how many miles per gallon you are getting. Some cars actually calculate it for you as you are driving. But if yours doesn’t calculate the miles per gallon, you can easily do it yourself (although not “on the fly” as you are driving).
Note: This is a typical math problem and so if you are working on a math problem that doesn’t give you start and end mileage see the comments at the bottom.
How to Calculate Miles Per Gallon
Simply fill up your gas tank (make sure it is full i.e. the pump shuts off) and write down the mileage from your odometer. Then the next time you fill up (make sure it is as full as it was the first time) and write down the number of gallons (from the gas pump) and the mileage again from your odometer.
Calculating Miles Per Gallon (mpg)
Now you have three numbers on your piece of paper, they are:
- Miles at the start of the tank (first fill)
- Miles at the end of the tank (second fill)
- Gallons used
Here is the formula for calculating Miles per Gallon (MPG):
(end – start) = miles driven
Miles Driven / Gallons Used = MPG
So:
The Miles per Gallon Formula is:
If you’d like to see the average cost of gas in the U.S. or how gasoline prices have compared to overall inflation see Inflation adjusted Gasoline Prices.
Once you know your average miles per gallon (mpg), you can use our Cost of Gas per Month calculator to estimate how much you are spending on gasoline in an average month from this it will estimate your average cost of gas per year as well. By knowing how much you spend on gas you can get a better handle on your monthly commuting expenses and your overall budget.
See Also:
- Cost of Gas
- Calculating the Cost of Gas per Month
- Gas Prices (nominal and inflation adjusted)
- Crude Oil Prices (table)
- Oil Price History (Chart)
- Cost of Living comparison between any two cities in the U.S.
- Rate of Inflation
- Inflation Adjusted Gasoline Prices
- Gasoline vs. Crude Oil Prices
- Historical Gas Price Chart
- Current Average Cost of Gas by County
- Gasoline Taxes by State
- Average Cost of Gas Per Month
- Regarding Gas Inflation
- Gasoline Rewards Credit Cards
- More Inflation Adjusted Prices
Image courtesy of Salvatore Vuono/FreeDigitalPhotos.net
our car gets about 20 miles per gallon. You are planning to drive to see your friends who live about 850 miles away. How many gallons of gas will you need to purchase to make the trip to see your friends and to return home? can someone help me please. this is for a math pert test
If this is an Algebra class you should use the algebraic formula. You should also remember that the word “Per” means “divided by” so Miles per Gallon = Miles/Gallons. You can always start with something like miles/Gallons= miles/Gallons then rearrange them until you get what you want all by itself on one side of the equation. If this is just a word problem and you don’t have to use algebra you can just substitute the numbers into the formula we just created. MPG=miles/gallons so 20mpg = 850 miles/? gallons if we divide both sides by 850 we would get 20/850 = 1/gallons but we want Gallons not 1/gallons, so we would need to invert both sides and get 850/20 = gallons /1 = ? so the answer is 850/20 = 42.5 gallons. You can check this by plugging all the numbers back into the formula. 20 mpg = 850 miles / 42.5 gallons. 850/42.5=20 so it works!
If a car traveled 273.6 miles on 9 gallons of gasoline how many miles could his car travel in 1 gallon
The first step is to calculate Miles PER Gallon. Always remember “Per” means “divided by” so Miles per Gallon means Miles divided by gallons. So (273.6)/9= 30.4 So for each gallon you can go 30.4 miles. In this case, the question asks how far you can go on one gallon so you are done. The answer is 30.4 but if it asked how far you could go on 2 gallons you would multiply 30.4 times 2 or however many gallons they give you. Hope this helps!
If I buy 7.2 gallons of gas for 19.08. What was the price of one gallon of gas?
The formula is $ = ($/gal) * gal
Which makes sense because if we look at the right side of the equation the gallons would cancel out and leave you with just Dollars which is what is on the other side.
Total Dollars = Cost per gallon times the # of Gallons
If we know any 2 we can figure the 3rd one.
So we know total cost and # of gallons
$19.08 = ? x 7.2
so we divide both sides by 7.2
$19.08 / 7.2 = ?
I still don’t understand
Sorry, I’ll try again. Whenever you see the word “per” you can substitute the words “divided by” so “miles per gallon” can be translated into “miles divided by gallons”. So if you drive 50 miles and it takes you 2 gallons you take 50 divided by 2 and get 25 miles per gallon. Miles/gallons=MPG.
Hope this helps.
Haley bought a new truck for her landscaping business. She loves that it has space for all her equipment, but she wishes it got better gas mileage. She only gets 18.4 miles per gallon on the highway. If her gas tank holds 20.5 gallons, how far can she drive with a full tank???
To calculate this you multiply the Miles per gallon times the number of gallons. Remember that “per” means divided by so the formula is (Miles / Gallons) x Gallons so the gallons cancel out and you are left with miles driven.
What do you get if you split the number 1943 in half?
971.5 or 971 1/2
Okay my gas gauge is broke and I put $25 worth of gas in at a $1.79 gallon how many gallons would that give me and how do I calculate that
Zayda, Your gas gauge has nothing to do with the calculations. The formula is Cost = cost per gallon times gallons or Total $= ($/gal)*Gal the tricky part is getting the cost and the gallons to switch sides in the formula. It gets really crazy if you try to move the Gal but if you move the ($/gal) it’s easy. So you divide both sides by ($/gal) and you get Total $ / ($/gal)= Gal or $25/$1.79 = 13.966 gallons
How many times will I fill up a uhaul truck 40 gal tank 17ft truck and it get 10 miles per gallon going 869.1 miles
Lorraine,
This is a two step process first you need to calculate how many gallons you will need. To do this you divide miles by miles per gallon. The way you figure that this is the right formula is like this: Gallons= (G), Miles= (M), Miles per Gallon = (MPG) Per means divided by so MPG=M/G. So somehow we need to rearrange the formula so that we get G= something. We could just turn them both upside down and get 1/mpg=G/M then if you multiply both sides by M you get M/mpg=G or Gallons=M/mpg. So if you have 869.1 miles divided by 10 mpg you get 86.91 gallons. Since you have a 40 gallon tank you are going to need 2 full tanks and 6.91/40ths of a tank or say 7/40 or if you get a bit worse mpg maybe another 1/4 of a tank. But you aren’t going to be able use every last drop of gas before you refill so say you use 30 gallons and refill when you have about 1/4 of a tank left. That means you can go about 300 miles before you have to refill. 30 gal x 10 mpg = 300 miles. Remember MPG= Miles / Gallons so mpg=M/G this time we want Miles= something so we can just multiply both sides by gallons to get rid of the G on the bottom. So G x mpg = Miles. So you start with a full tank (the truck will probably only have a half a tank so you have to go straight to the gas station before you start. Then you drive 300 miles and fill up again (getting about 30 gallons), then you drive another 300 miles (30 more gallons) and fill up again trying to get it so you have a half tank left in the truck. Total gas used about 87 gallons.
How many miles can you drive a pick up truck on a gallon of gas if it was made by Ford a newer pick up truck
According to FORD statistics an F-150 gets “Up to” 19 city / 26 highway since these are generally optimistic and you drive a combination of both you could guess that you would get about 20 to 21 miles on a gallon of gas.
Im driving from Richfield ,Mn to Winchester , Va. 16 hr drive -34 mpg – $2.09 a gallon- 1,060 miles. How many times will I need to fill my gas tank one way?
If you get 34mpg and drive 1060 miles it would take you 31.2 gallons. The cost per gallon doesn’t have any bearing on this problem but the size of your tank does. Obviously, if you have a 35-gallon tank you would only have to fill up at home and once you arrive. But if you have a 16-gallon tank you would have to fill up once in the middle. Except you never want to get down to the last gallon so you would probably want to fill up twice.
When taking a trip I use the gas Buddy Trip App it not only tells you how many times you need to fill up it also calculates the best places to fill up (based on price) along the way. It even asks you what model car you are driving so it will know what size tank you have. You can find it here: https://www.gasbuddy.com/TripCostCalculator
How do I figured how many gallons I will need for a trip
You need to know how many miles per gallon your car gets. If your car gets 20 mpg and you drive 200 miles you might intuitively guess that you need 10 gallons but how do you figure that? Miles per gallon means miles divided by gallons which is commonly written as mpg but also can be written m/g. So the formula is m= (m/g)*g because the g’s cancel out. So if you want to know g you have to move the m/g to the other side of the equation. To do that you multiply both sides by g/m. So the new equation looks like this: (g/m)*m= (g/m)*(m/g)*g so you cancel (g/m)*m=
(g/m)*(m/g)*g resulting in this (g/m)*m= g which is the same as m / (m/g).So Gallons = miles divided by mpg. or 200 miles / 20 mpg = 10 gallons.
Tim,
If my annual gas cost was $860.31 and my tank holds 25 gallons and I paid an average of $2.00 per gallon and I average 15 miles to the gallon then how many miles were driven in 1 year?
Thanks,
BK
Brad, Tank size is irrelevant.
Total Cost / (cost/gal)= gallons
Gal x (Miles/Gal) = Miles
So in your case that would be:
$860.31 /$2 = 430.155 gal
430.155 x 15 = 6,452.325 miles
The key is to sort your units so they cancel out and remember if you divide you invert and multiply.
how much will it cost me to drive 90-getting 10 miles to gal.at $4.00 a gallon?
To figure this out is a two step process. First how many gallons would you use?
To drive 90 miles getting 10 miles per gallon you would use 9 gallons.
90 miles / 10 mpg= 9 gallons
Why Divide by mpg?
Always remember mpg means miles per gallon and “per” always means “divided by”.
It always helps to sort out the units so you can find out the formula.
MPG could be written as m/g. So the units would be as follows: miles / (miles/gallon) = gallons.
Why? Invert and multiply. So miles / (miles/gallon) also equals miles x (gallons / miles)
Since you have one “miles” on top and one on bottom the miles cancel and you are left with gallons.
To find the answer (Dollars) use the formula: gallons x (Dollars per gallon) = Dollars
So 9 gallons at $4/gal = 9 x 4.00 = $36.00
Hope this helps!