Maths genius required!

-Mike-

-Mike-

-Mike-

Soldato
Joined
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Minehead
Hey all,

Can anyone work this out for me, or give me the workings to figure it out?

Car mileage 41017 average mpg 48.6.

What mpg would it take to increase that figure to 48.7 when you've only travelled 26 additional miles? I'd reset the trip and see but I'm currently being clocked for work mileage so can't reset it until they pay me at the end of the month!

Trying to see what difference the EGR clean has had!
 
41017 miles at 48.6 mpg = 41017 / 48.6 = 843.97 gallons consumed.

You want 48.7 in an aditional 26 miles?

Then (41017 + 26) / 48.7 = 842.77 gallons consumed. That's less than what the car has already consumed, so platinum is right. It's not possible. You would have to drive those 26 miles whilst consuming a negative amount of fuel.
 
SlyReaper said:
41017 miles at 48.6 mpg = 41017 / 48.6 = 843.97 gallons consumed.

You want 48.7 in an aditional 26 miles?

Then (41017 + 26) / 48.7 = 842.77 gallons consumed. That's less than what the car has already consumed, so platinum is right. It's not possible. You would have to drive those 26 miles whilst consuming a negative amount of fuel.
Click to expand...

What I meant was - I have covered 26 miles and its pushed that average up 0.1 so am wondering how I could calculate the MPG its achieved to push that average up.

I should add, and have probably left out something very important. That average reading is based on a trip reading of 2700.5

So Reading at 2674.5 was 48.6

Reading at 2700.5 is 48.7

Does that help?
 
Ok so i've figured it out.

Your initial MPG was 48.69999999999999999999999999999999999999999999

Your new MPG is 48.700000000000000000000000000000000000000000000000000001
 
-Mike- said:
What I meant was - I have covered 26 miles and its pushed that average up 0.1 so am wondering how I could calculate the MPG its achieved to push that average up.
Click to expand...

the other poster you've quoted has already answered that... assuming it was exactly 48.6 and jumped 0.1 from an additional 26 miles.... in reality its only accurate to 0.1... so hasn't necessarily


I should add, and have probably left out something very important. That average reading is based on a trip reading of 2700.5

So Reading at 2674.5 was 48.6

Reading at 2700.5 is 48.7

Does that help?
Click to expand...

who cares... your previous reading was closest to 48.6 now its closest to 48.7... maybe the actual mpg figure was close to 48.649 etc...
 
OP unfortunately such a calculation is just impossible.

Firstly, when the car is new it will have better MPG

It will then get worse, when you service it, it will be better but prob not as good when it was new.

But there is no way to calculate this properly as its never an exact useage. One day you might be revving like a lunatic, one day you have aircon and radio blasting etc

What i mean is you cannot calculate it past the first decimal point accurately, only past but never future.
 
41017 miles at 48.6 mpg = 843.97 gallons consumed.
41017 - 26 = 40991 miles at 48.7mpg = 841.70 gallons consumed.

So, 2.27 gallons consumed in the last 26 miles.
=11.45mpg


As most people have said though, the trip computer is not accurate enough for this type of calculation.
 
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I thought that the average MPG counter is not usually cumulative anyway, it's calculated on the basis of the last X miles, and so the calculation above doesn't really apply. If you go and drive it down the motorway at a moderate speed (60) for a while you'll see the average MPG going up.
 
platinum87 said:
OP unfortunately such a calculation is just impossible.

Firstly, when the car is new it will have better MPG

It will then get worse, when you service it, it will be better but prob not as good when it was new.

But there is no way to calculate this properly as its never an exact useage. One day you might be revving like a lunatic, one day you have aircon and radio blasting etc

What i mean is you cannot calculate it past the first decimal point accurately, only past but never future.
Click to expand...

Your statement regarding a car having its best mpg when new is wrong. I don't understand the maths stuff to calculate this but I can tell you that a car doesn't have its best MPG when its brand new at all.

Infact, its probably near its worst mpg due to tightness of new components.
 
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