[jaccia]

What is the conversion to get from kilometers to liters?

[typhoon2028]

Take kilometers divide by pi.  Then multiply by 6.4.  (I'm joking)

You do know that kilometers are an unit of distance, and liters are an unit of volume?

[jaccia]

I am trying to do the following:

In Europe, gasoline efficiency is measured in Km/L, If your car's gas mileage is 30.0 mi/gal, how many liters of gasoline would you need to buy to comlete a 142km trip in Europe?  1 km=0.6214mi  , 1 gal=3.78L

30.0mi/1 gal * 1 km/.6214mi* 1 L /142km* 1 gal/3.78L

So, i know the 1 L /142 km is wrong, how do i set this up correctly?

[Doc Oc]

Take kilometers divide by pi.  Then multiply by 6.4.  (I'm joking)

You do know that kilometers are an unit of distance, and liters are an unit of volume?

Ha ha!  I was wondering if I had read the title correctly.

Jaccia, it's more simple than you're making it.  The easiest way is to convert each unit individually and then slap them on top of each other to get the proper ratio.  But the dimensional analysis you posted is correct except for the 1L/142 km, why is that there?  142 is a separate calculation.  The dimensional analysis converts mi/gal to km/L.  Once you know how many km you get per L, then apply the 142 km/x L.

[sjb]

How many miles is 142 km?

[jaccia]

I do not understand either post.  Get rid of the 1/142 km , ok

Then when i cancel and multiply i get 12.8

Take 12.8/1 L * 1 L/142 km =.09 but all the meters cancel each other out...what am i doing wrong?

[Doc Oc]

Why are you putting 142 km/1 L?  You aren't trying to drive 142 km on 1 L, you need to solve for the number of L, so you should have 142 km/x L (x = number of liters you will need to travel 142 km).  So once you've converted 30 mi/1 gal into km/L, then apply that ratio to 142 km/ x L.

[jaccia]

So do i set it up as follows:

12.8 km/1L * 142 km/xL=

12.8x km/L / 12.8 = 142 km/L /12.8

x = 11.09L  Is this the answer?

[Doc Oc]

Yes that's the correct answer, but the first line you put up isn't correct.  It should be:

12.8 km/1L = 142 km/x L

Your other calculation/equation is correct.

[Borek]

In Europe, gasoline efficiency is measured in Km/L

Huh? What idiocy. We use L per 100 km.

[JGK]

In Europe, gasoline efficiency is measured in Km/L, If your car's gas mileage is 30.0 mi/gal, how many liters of gasoline would you need to buy to comlete a 142km trip in Europe?  1 km=0.6214mi  , 1 gal=3.78L

I find it quite odd that for a problem set in Europe they've given you the US gallon to litre conversion factor.

Theres also the UK (which was in europe the last time I looked) Imperial Gallon which is equivalent to 4.55 L

[DrCMS]

If your car's gas mileage is 30.0 mi/gal

They've also given American fuel consumption figures; if my car only gave me 25mpg for a ~90 mile trip I'd take it to a garage to get it fixed.