In the last few years people have started using phrasing I don’t understand. it’ll go like this;
John makes three times less money than Jane. So if Jane is making $24/Hr then how much money is John making an hour?
It’s terrible phrasing I know.
I would assume it means a third, so John would be making $8/hr.
Yeah, I think it’s just an unfortunate (and somewhat nonsensical) reversal of the phrase, in this case: “Jane makes three times as much money than John.”
I agree with Richard; John is making $8/hour, in your example.
It’s meaningless, without specifying a third earner (let’s call her Judy) who is making no more than $31.99/hour (and no less than $24.01/hr).
If Judy is making $26/hr, Jane is making $2 less per hour. John is making three times less than Jane, so $6 less per hour than Judy; therefore, $20/hr.
I have heard tell of people who insist that language does not follow the rules of mathematics, and that “three times less” means “one third as much.”
I have also heard tell of people who think that oysters are made of food, and that pitchers who return to the field after someone has taken an at-bat for them are playing baseball; these people are wrong, too.
Would be better with “as” in place of “than”.
But it’s much superior to “three times more than”, which is not quite as bad as what the OP mentions, but still quite bad (and depressingly common).
But at least “three times more than” has an easily determined quantity (four times as much as) without the need to invent or plead for a third point of reference.
Eh. . . see ‘recency illusion.’ That type of phrasing definitely goes back over 100 years. Also see ‘idiom.’ 
The problem is, almost nobody (at least in my experience) uses the phrase “three times more than” to mean “four times as much as.” It’s generally used to mean “three times as much as.”
It is language, not maths. It means what the speaker intends it to mean. This is most likely to be “a third”. The fact that it is ambiguous shows it is poor use of language, but it’s not like you have absolutely no idea of what the speaker could possibly mean.
Thank you for the info.
Okay, then lets try a variation on this phrasing I hear sometimes.
When they say John makes 50% less than Jane, and Jane makes $24/Hr then how much money does John make an hour?
I want to be clear since I guess this how we are going to be expressing ourselves from now on.
$12/hr is the number I assume the speaker or writer would be getting at there.
In uni. I minored in statistics - It was a huge offence to use that kind of phrasing for exactly the reasons everyone discusses.
You now see this kind of phrasing often in the media. I think it’s because the word “times” makes the difference seem bigger than it really is. “Three times less” seems to people to be a bigger difference than say “one third”.
It’s now a pet peeve of mine, but I’ve given up trying to correct people unless I really need clarity (like in a business meeting). When I see this, I now assume that the person using it really doesn’t understand math or statistics or their proper terminology. If they’re educated in it, they’d never use that phrasing. Since they’re not educated, I then completely discount whatever they’re telling me.
See my points above regarding oysters, baseball, and wrongness.
If an idiomatic expression CAN be expressed in mathematical notation, then THAT expression is the preferred (and therefore, RIGHT) one.
The so-called ambiguity “problem” can be eliminated by eliminating the underlying problem, which is the poor use of language that enables its existence. And THAT will be practical only through the refusal of those who recognize that it is poor usage to tolerate it.
Your responsibility has been established and elucidated, sirrah. It is now down to you to accept or to reject the task with which you (or more precisely, we) have been charged. I make no representations that this task will be easy, merely that its fulfillment is both worthwhile and necesssary, and I ask you if you are equal to the challenge.
ETA: mods, I hope that the above does not violate the Board’s strictures against calls to action. In the event that it does, please accept my most abject apologies.
For extra fun, throw temperature into the mix! This object is twice as hot as this other object. January the 12th was four times as cold as Christmas Day!
Umm, uncle…
I hate the “three times less” locution. Sure, it’s generally clear what the person is trying to say, but it’s really poor usage.
Want to see something even worse? A book i read a while back was dealing with a set of numbers where the total dropped from 1,333 to 321. The authors argue that “this amounts to a decline of four hundred percent.”
A decline of four hundred percent? Sorry, but if we’re talking about physical things where there can’t be negative numbers, a decline of one hundred percent is the absolute most that you can have.
I think this usage, specifically involving per-cent numbers, is standard. It means:
(1) Compute 50% of $24.
(2) Subtract that from the original $24.
(3) What you have left is the answer.
More generally, “x% less than y” means:
(1) Compute x% of y.
(2) Subtract that from the original y.
(3) What you have left is the answer.
Algebraically: “x% less than y” means: y - ( (x/100) * y )
or equivalently: y * ( (100-x) / 100 )
Note that this computation applies specifically when fractions are expressed as per-cents.
Per-cents, of course, are just another way to write fractions (besides common fractions and decimal fractions), but they come with their own vocabulary.
50% is exactly synonymous with ½, but if we say “½ less than 24” it means just 23½
But if we say “50% less than 24” it means 12.
I found the following opinion piece by poet Jan Freeman who claims this confusion is recent.
“Times has now been used in such constructions for about 300 years, and there is no evidence to suggest that it has ever been misunderstood.”
I can’t comment on the ease of use for most people, but ‘Three Times Less Than X’ easily maps to X/3 in my mind before I even get to the X.
Here is a cite showing it has been used for quite a while, and I have changed the long s (ſ) so that modern readers don’t hit the fffff-stop
This is from Issic Newton’s 1730 book Opticks
Could it be phrased in a way that is clearer, probably.
Is it a new or novel use? No.