We're doomed

[Hawkmoon]

Higher math stumps thousands

https://www.dailymail.co.uk/femail/real-life/article-11598369/What-think-550-divided-two-is.html

[WLJ]

"Higher"   
275 popped into my head automatically.

But in the name of equity anyone answering 225 or any other answer or even no answer will be given the same grade as those answering 275. Trophies for everyone!

[Brad Johnson]

Simple division is higher math now?

Brad

[230RN]

We learned a lot of math shorties at Brooklyn Tech in the late forties and early fifties.  One of them was to break the problem into digestable segments.

"Half of 500 is 250 half of 50 is 25, sum = 275," as an example, viz WLJ.

Terry, 230RN

[K Frame]

Ask the same people to read an analog clock.

I bet a significant number of them would have a stroke.

[HankB]

We should locate every math teacher^* who passed these people along and claw back a portion of their salaries, since they clearly didn't do their jobs and - by issuing passing grades certifying a certain level of competence - falsified records.

* OK, every math teacher past 3rd grade.

[Nick1911]

As Terry mentioned, I divided the problem as half of 500, and half of 50.

I do somewhat frequently have to do mental math like this in the metal shop.  Measure a diameter, figure out how much per side I need to cut on the lathe, for instance.

I tried long division and largeish multiplication on paper a fer years ago.  I could do it, but division took me a second to get back into the swing of it.

At one point Iearned how to do square roots on paper. That's gone.

My calculus is shaky.  I don't remember all the identities you need to get from point a to b.

One thing I wish I had learned in grade school which would have been useful in future education is shorthand. 

[230RN]

Multiplying by five is easy.  Move the decimal (multiply by ten) and take half of that.

In the 550 case, we're already "halfway" there with 275.  Now, times 10 =2750.

550 X 5 = 2750.

Ta-dahhh!

Now if h. sapiens had developed with 11 fingers, we'd be in baaaad trouble.

[Nick1911]

Now if h. sapiens had developed with 11 fingers, we'd be in baaaad trouble.

Thread veer:  If humans had 11 fingers, would we have a base 11 numeric system?

[cordex]

Thread veer:  If humans had 11 fingers, would we have a base 11 numeric system?

Did the Sumerians have 12 fingers?

[Perd Hapley]

Did the Sumerians have 12 fingers?

I thought they had 60.

[Pb]

I read speculation about why the Sumerians used base 12.  It is the highest number that can be easily counted on one hand.  Touch your thumb to each finger tip (4).  Then touch your thumb to each of your first finger joints (4 more).  Then touch your thumb to each of your second finger joints (4 more).  12 total!

[cordex]

I read speculation about why the Sumerians used base 12.  It is the highest number that can be easily counted on one hand.  Touch your thumb to each finger tip (4).  Then touch your thumb to each of your first finger joints (4 more).  Then touch your thumb to each of your second finger joints (4 more).  12 total!

That's just gross.

[Ben]

That's just gross.

To the Elventyone!

[HeroHog]

That's just gross.

I see what you did there...

[K Frame]

I read speculation about why the Sumerians used base 12.  It is the highest number that can be easily counted on one hand.  Touch your thumb to each finger tip (4).  Then touch your thumb to each of your first finger joints (4 more).  Then touch your thumb to each of your second finger joints (4 more).  12 total!

Unfortunately, mine would be a base 8 if that were the case.

Damned arthritis...

[Perd Hapley]

based

[lee n. field]

Did the Sumerians have 12 fingers?

<tinfoil>Maybe some did</tinfoil>

[lee n. field]

I read speculation about why the Sumerians used base 12.  It is the highest number that can be easily counted on one hand.  Touch your thumb to each finger tip (4).  Then touch your thumb to each of your first finger joints (4 more).  Then touch your thumb to each of your second finger joints (4 more).  12 total!

use binary, reach 32.  (11111)

[MechAg94]

We learned a lot of math shorties at Brooklyn Tech in the late forties and early fifties.  One of them was to break the problem into digestable segments.

"Half of 500 is 250 half of 50 is 25, sum = 275," as an example, viz WLJ.

Terry, 230RN

I would do what you did.  Part of the basic skill of math is to break the problem into smaller problems that you can easily solve.  (teaching you to logically think)  I guess kids aren't taught that anymore.  I recall college professors that were very good at doing big physics equations in their head by rounding up and down all the numbers and getting within 10% of the exact answer in the end.  Most everyone memorized all the single digit multiplication tables so break your problem down to that point.   

The confusing thing to me about the article is why people think the answer is 225.  Is this some sort of common core thinking?  Maybe they think 2 + 2 = 5?

Maybe the other question is do students spend much time doing multiplication and division on paper?  You can line up 550 / 2 on paper and do it the long way easily enough to prove your answer. 

[HankB]

I read speculation about why the Sumerians used base 12.  It is the highest number that can be easily counted on one hand.  Touch your thumb to each finger tip (4).  Then touch your thumb to each of your first finger joints (4 more).  Then touch your thumb to each of your second finger joints (4 more).  12 total!

For ancient merchants and traders, maybe base 12 made some sense. For example, with base 10, you can divide 10 evenly into 1, 2, 5, and 10 parts - so that's one tenth, one fifth, one half, and one whole. If you work in base 12, you can divide evenly into 1, 2, 3, 4, 6, and 12, so that's one twelfth, one sixth, one quarter, one third, one half, and one whole. So base 12 makes sense if you're in a business that requires divvying things up.

[bedlamite]

I read speculation about why the Sumerians used base 12.  It is the highest number that can be easily counted on one hand.  Touch your thumb to each finger tip (4).  Then touch your thumb to each of your first finger joints (4 more).  Then touch your thumb to each of your second finger joints (4 more).  12 total!

Using binary, it's easy to count to 1023 on your hands.

[RoadKingLarry]

My wife threw an absolute fit when I tried teaching my children hexadecimal when they were still in elementary school.

[Perd Hapley]

https://www.thoughtco.com/why-we-still-use-babylonian-mathematics-116679

[230RN]

Then there's the old joke about why programmers have only nine fingers.  Since zero is a number, they count them starting with zero.