Yes definitely. Although it might be helpful in explaining what an "independent" variable is to say that sometimes the experimenter controls it.

Both "control variable" and "independent varable" are sometimes, very confusingly, called a "controlled variable".

My take is that there is a muddle here. There is a thing called a "control variable" which is a quite different concept - something that is held constant so that it doesn't affect the response. What is being talked about here is I think more properly called an "independent variable".

Or training wheels or arm bands, or even nappies!

I'll be there.

I had a Glaswegian friend at university. At least I think he was a friend, but since I never understood a word he said, I can't be sure.

But wouldn't a comma be right here, rather than either of these?

It was blowing half a gale when the puppy went out for a pee. He cocked his leg, but he has only just learnt to do this, so he's not very good at it. He blew right over! Poor pup. Nothing hurt but his dignity.

This is a must-read.

This is so, so well-articulated.

Crossing 7s isn't much of a thing here in the UK, I guess because it's what the French do, and we wouldn't want to copy their habits. Also they put big ceriphs on their 1s, which we don't, so we don't need to cross 7s. But we cross our zs, to stop them looking like 2s. Is that a thing with you?

Well well. It's easier to prove than it looks as thought it might be, and I'm now annoyed with myself for not seeing it earlier: spent too long playing with Geogebra!

Ahha! So the sign writer for the lift on my hotel made too mistakes.
1 Left off the Max, so the sign is pretty mycn meaningless
2. Failed to notice that the maix for this lift is 13

This a a great puzzle. I've solved it by construction. Sliding that point around the quarter circle, geogebra says the angle is always 45˚. Still need to find a proof.

I've been reading the output of the solar powerstation on my roof every quarter for 15 years. Here is a summary (in kWH)

Q1 Q2 Q3 Q4
Mean 488 1082 911 229
St Dev'n 198 161 103 63

What do you notice? What surprises you?

I'm pretty sure that means don't use the lift in a fire.

The #mathsonholiday tag is underused! This lift is interesting for another reason. It moves rapidly between floors (we were in the 8th) and must have high accelerstion, but one has little sensation of that. I think it must have low jerk. Do engineers consider jerk in such situations?

A diagramtic man and woman stand next to a squiggle at floor level.

Has anyone got any idea what the top left group of symbols in a lift in a hotel in Malta means? My family has only managed scatalogical explanations. That squiggly thing looks like an 8 on its side, but elsewhere it says the max capacity is 13 persons.

Brilliant! I've been wondering how to approach this topic with my granddaughter. She keeps asking me about infinity, and I've been failing to find a way in that is both accessible to her and also true. Now I have one.

Well it is certainly an interesting example. Thanks.

Do you have an example?

Subtracting Left to Right YouTube video by Jim Simons

Your occasional reminder that subtracting left to right is SO much easier than right to left
10-4 = 6, but 33>01, so 5
0-3 = 7, but 1>3, so 6
1-3 = 8
Therefore 568

youtu.be/wWxdPAQSgzo?...

This worked brilliantly for me: there is really no better way to deeply understand something than to teach it. Whether it worked for him I can't say, but I hope it can't have been terriible to have a tutor on hand in all his maths lessons.

The school I attended had the really weird idea of putting in the same class some boys who were covering 3 years' content in 2 years, and some who were covering 2 years' content in 3 years. I sat next to a lad in the second category, so did a lot of explaining to him...

Geometry says that if there is restricted space to approach and manoeuvre (more common here in the UK), it is easier to back in and come out forwards.

And of course the right angle was Euclid's unit of angle, before the degree became standard. I was puzzled at school to learn that the sum of the angles in a triangle is 2 right angles. Why not 180°? Because that's how Euclid had it.

We both have 98/192.

Excellent. Since the answer must be of the form n/192, if we agree to several decimal places then we agree!

Here's my strategy, which I think is optimal, although there are ties. Coins a b c. a mean toss a, A means call A.
ahahA
ahatb(hB,tC)
atbhb(hB,tC)
atbtC

Ok, so I found some time and some paper. I reckon the overall chance I call right is 49/96. Feels about right, but I've probably made a mistake aking the way. Anyone else got an answer?