No, of course not. Know when to pick your battles!
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Purely by chance, I was browsing the New Scientist website a few minutes ago and noticed the following under their heading of ‘Mathematics’
How maths reveals the best time to add milk for hotter tea
If you want your cup of tea to stay as hot as possible, should you put milk in immediately, or wait until you are ready to drink it? Katie Steckles does the sums
By Katie Steckles
3 May 2023
I don’t subscribe, so I don’t know what their article reveals.
Might be worth a look ?
I’ve just ‘Googled’ this subject of milk/tea. Seems like the entire nation (and more) have studied the subject … other than Mrs D 
I don’t subscribe either but the article has a picture of a mug with a graph on it that explains everything.
Maybe buy the mug and make a cup of tea in it for Mrs D?
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On a similar note, I have a cup of tea and a cup of milk. I put a spoon of milk into the tea, stir it, and add a spoon of that mixture to the milk.
Do I have more tea in the milk, or milk in the tea?
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Nice teaser jr.
I’m pretty sure some of us know the answer, so are holding back to give others time to think this one through.
I use coloured discs to illustrate my explanation, and i’ve seen others use marbles.
Of course, maths does a good job but often causes more confusion than conviction
Stir it
JR, that is a neat addition. (ok, it is often included in the teaser) It steers the reader into a visualisation that, to my mind at least, makes it difficult to focus on the whereabouts of the milk that was added to the tea.
Of course, it doesn’t matter whether the tea/milk is stirred or not. The answer is still the same.
As an Apple user for some 30+ years I wholeheartedly agree. I can’t remember how many times Microsoft surprised me with another annoying new thingie at work. Windows 10 is admittedly very much better, as is our Surface laptop.
My standard search engine is Ecosia on both, iPad and laptop. Somehow the old iPad never managed to remember that preference.
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That is a good brain teaser, jr.
There is exactly the same amount of tea in the milk as there is milk in the tea.
I’ll provide a few slides to illustrate my reasoning.
This first picture shows two mugs, one with milk and one with tea. Think of the discs as “molecules”
The second slide shows a nominal amount of milk (5 ‘molecules’ =a teaspoon) has been moved to the mug of tea.
The tea/milk mixture (in the right hand mug) has now been ‘stirred’, but you can see where each ‘molecule’ of milk is !
I have highlighted (Slide 4 above) the ‘teaspoonful’ of mixture (tea/milk) that I am about to transfer back to the mug of milk.
You can now see (Slide 5 above) the highlighted ‘teaspoonful’ of tea/milk now in the ‘milk-mug’.
And finally, you can see two 'molecules of tea in the milk mug, and two 'molecules of milk, still remaining in the tea mug.
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Very nice [visual] explanation, Don 
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It follows that well known physics principle of “conservation of tea”.
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Thank you Cluffy.
Well, Well, Well !!
Our neighbour has a well in his garden. It has a volume of 1.25π m³ and is fitted with a ladder that is 5m long.
Mrs D would like me to dig a well that is mathematically similar to our neighbour’s, but with a volume of 10π m³.
How long a ladder will I need to reach the bottom of my well ?
Bravo, Don. For the tea problem, knowing that the two cups wind up with equal volumes makes the solution pretty clear. If there were more, say, tea in the milk, the teacup would contain less liquid.
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Here’s a couple of variations on the tea teaser:
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What would the answer be if the initial amounts of tea and milk were different?
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What would the answer be if, having just stirred the tea, I then take a sip of tea?
(I hope I am not digging myself a 10 metre hole in the garden by distracting from Don’s latest teaser!)
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I think the ladder needs to be 10m long.
I’ll leave my workings until later to give others a chance to solve as well.
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I thought I had responded to Part (1) of Ravvie’s follow-up teasers to JR’s Milk/Tea teaser, but i don’t see it. I’ll post my response again later today.
Meanwhile, it looks like both Ravvie and Steve have solutions to the Well, Well, Well teaser. Ravvie’s is correct and i’ve no doubt so is Steve’s.
If anyone else is still giving it some thought, bear in mind that the words ‘mathematically similar’ mean same shape and proportions.
I think the result in this situation would be the same regardless of the initial quantities of tea and milk ie there would be the same amount of tea in the milk as there was milk in the tea.
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