Asklemmy

43452 readers

981 users here now

A loosely moderated place to ask open-ended questions

Search asklemmy 🔍

If your post meets the following criteria, it's welcome here!

Open-ended question
Not offensive: at this point, we do not have the bandwidth to moderate overtly political discussions. Assume best intent and be excellent to each other.
Not regarding using or support for Lemmy: context, see the list of support communities and tools for finding communities below
Not ad nauseam inducing: please make sure it is a question that would be new to most members
An actual topic of discussion

Looking for support?

Looking for a community?

Lemmyverse: community search
sub.rehab: maps old subreddits to fediverse options, marks official as such
[email protected]: a community for finding communities

~Icon~ ~by~ ~@Double_[email protected]~

founded 5 years ago

MODERATORS

[email protected]

why do a bunch of gas stations have 88 octane cheaper than 87? (lemm.ee)

submitted 2 months ago by [email protected] to c/[email protected]

42 comments fedilink hide all child comments

I figured it was a marketing gimmick to get you to buy 88 and then they would finally raise the price, but it's been years. are they adding extra ethanol or something?

you are viewing a single comment's thread
view the rest of the comments

[–] [email protected] 32 points 2 months ago* (last edited 2 months ago) (1 children)

E10 has an energy density of 108,608 BTU/gal and E15 has an energy density of 106,814 BTU/gal.

source: http://www.airimprovement.com/reports/national-e15-analysis-final.pdf

This gives us tha the 88 octane has 106.8/108.6 ≈ 0.983 times the energy density of the 87.

1-0.983 = 0.017

The correct number is that the 88 needs to be 1.7% cheaper than 87 to give equivalent distance per dollar.

LLMs are fantastic tech, good at many things. Math is not one of those things.