Purchase price: 24000
Avg km/year: 40000
L/100 km: 5.3
Price of gas (per L):1.30
I was wondering what the formula is to find out how much litres of gas the car would consume as well as the cost of the car.
I've tried numerous equations but somehow failed to step into the correct formula. Any help would be much appreciated.
P.S: The answer is: This car would use 10600.0 litres of gas and cost 37780.0 over 5 years.
Best Answer
If your gas consumption is $\ell\text{ L/}100\text{ km}$, it’s $\frac{\ell}{100}\text{ L/km}$, so in driving $d\text{ km}$ you use $\frac{d\ell}{100}\text{ L}$ of gas. If the price per litre is $p$, you spend $\frac{d\ell p}{100}$ on gas in driving those $d\text{ km}$. If $\bar d$ is your average yearly driving distance in kilometres, and $n$ is the number of years that you drive, then $d=\bar dn$, so over a period of $n$ years you use $$\frac{\bar d\ell n}{100}$$ litres of gas and spend $$\frac{\bar d\ell np}{100}$$ on that gas. Here $\bar d=40000$, $\ell=5.3$, $n=5$, and $p=1.30$. The total cost of the car over that period is just what you spend on gas plus the purchase price of the car, which is $24000$.