(Postscript) How far should I go for cheap gas?


After writing yesterday’s diary, I noticed something a little interesting and would like to bring up this topic again.

Let me tell you what I mean.


That’s what I mean.

To recap from yesterday, the criteria for what constitutes a bargain are.



Yesterday, we assumed that the standard price of gasoline was constant (143 yen/L), but now we looked at how the « marginal economical driving distance (km) » would change if we changed the standard price from 100 yen/L to 200 yen/L.


The results are as follows.

In other words, the higher the unit price of gasoline becomes, the lower the « Marginal Value Driving Distance (km) » becomes.

In fact, this is a natural thing when you think about it.

which I mentioned earlier.


is, in other words.


Therefore, the higher the unit price of gasoline, the higher the cost of transportation (round trip) to get to the station, and the more likely it is that the cost will fall.

I thought this result was very interesting.

Because, as I mentioned at the very beginning.


This is because it implies that

In fact, the lower the unit price of gasoline, the greater the savings. However, we are so preoccupied with the total price that we don’t notice this fact easily.