# Algebra being replaced by tables

#### hrs

Joined Jun 13, 2014
355
Hi,

The kid next door wanted some math help. He is 16 and the subject is trigonometry.

Trivial algebraic manipulations are done away with and they are replaced by a table. The table has two rows and as many columns as you think you need steps. How exactly it is that you can get from a = b / c to c = b / a is not taught. Apparently this method is taught internationally. This is all fine if you choose hospitality or psychology later on but not if you're actually going to need math later on, I would think.

So I wonder, is this going to carry over into college or are they going to fix this problem before that time?

#### peterdeco

Joined Oct 8, 2019
424
I hope they fix it. Otherwise, without a table they won't be able to solve Ohm's law.

#### jpanhalt

Joined Jan 18, 2008
11,088
But, there are "aps" for that.

In a chemistry class, I once asked a college junior with straight A average, if 13 g is 1 mole, how much is 2 moles. She reached for her cell phone. Instinctively, I grabbed it and repeated the question. Fortunately, she also had a sense of humor. I might have been charged with assault. That was in 2007. It's not new.

#### nsaspook

Joined Aug 27, 2009
9,053
Kids like mine (the ones that actually understand math and science) will rule the world. I'm not worried.

#### BobaMosfet

Joined Jul 1, 2009
1,917
Scientists will tell you we are getting smarter, that we 'evolved'. Fools. In the beginning we were as smart as we will ever be. This is why Adam could name every living creature, or the fact that the farther back in time you go, the more accurate the geometries of the pyramids and other amazing structures- why we cannot duplicate today what they did then.

We are getting stupider, not smarter- the evidence is all around. Thankfully, a few of us still seek understanding, knowledge, and wisdom. Sadly, we're the first ones that are killed during a regime change...

#### jpanhalt

Joined Jan 18, 2008
11,088
Scientists will tell you we are getting smarter, that we 'evolved'. Fools. In the beginning we were as smart as we will ever be. This is why Adam could name every living creature, ...
I can name every living creature too.

or the fact that the farther back in time you go, the more accurate the geometries of the pyramids and other amazing structures- why we cannot duplicate today what they did then.
Not from what I have seen in early archaeology. For pyramids, here is some history: https://en.wikipedia.org/wiki/Egypt... pyramids,other archaeological remains of the

#### hrs

Joined Jun 13, 2014
355
I hope they fix it. Otherwise, without a table they won't be able to solve Ohm's law.
Well, it's not a look-up table or anything like that. The table, created by the student, holds partial solutions for each operation until all operations are done. The method will work, but imo it obfuscates algebraic relations and reduces insight into what you are doing.

#### atferrari

Joined Jan 6, 2004
4,506
As a Chief Officer in vessels, when a Loadicator (analog computer dedicated to calculation of stability, trim, stress and bending moments), was not available, it was necessary to calculate all that by hand . You could do it in around 30 to 50 minutes non-stop depending of the number of cargo spaces, tanks and parcels of cargo to take or discharge.

I witnessed the arrival of PCs and even programmed three of my different computers for that. Even more, the classification societies, made them compulsory and dedicated to that task (to minimize the risk of being affected by viruses, which in common freighters are a crowd).

Never in 30 years I've seen any Chief Mate doing that again.

The humble "trimming table" that allows you to calculate the effect on the trim when loading/discharging small amounts of weight, say 100 to 400 MT, seem to be a rarity nowadays. I even prepared (calculated ) the table myself for my own use during a whole contract and left it on board for the next guy.

BTW, a Loadicator, the analog original thing I mean, was the biggest (and warmest) festival of op amps that you could find anywhere. With several tens of knobs and buttons. A marvel.

#### MrAl

Joined Jun 17, 2014
8,604
Hi,

The kid next door wanted some math help. He is 16 and the subject is trigonometry.

Trivial algebraic manipulations are done away with and they are replaced by a table. The table has two rows and as many columns as you think you need steps. How exactly it is that you can get from a = b / c to c = b / a is not taught. Apparently this method is taught internationally. This is all fine if you choose hospitality or psychology later on but not if you're actually going to need math later on, I would think.

So I wonder, is this going to carry over into college or are they going to fix this problem before that time?
Can you show these tables so we can take a look?

#### DickCappels

Joined Aug 21, 2008
8,151
A few years ago my neighbor's daughter had failed business math on her second attempt and this was all she needed to graduate from her prestigious college in Bangkok . Her dad was ready to throw in the towel when I volunteered to see if I could help.

The major part of was differential calculus which, the principles of which she seemed to grasp, but algebra...that was very frustrating for me. I would say "How do we get this over there by itself" and then she would recite a rule she had learned and then go through the motions. She had no concept of what algebra was about, but was able to memorize processes to solve "standard" problems.

At one point she picked up her calculator when I said "Three plus 8, what is that?" Which was quickly followed with "No! You don't need a calculator for that!"

When her dad told me that she passed the final exam I was completely stunned.

Kids today, huh?

#### hrs

Joined Jun 13, 2014
355
Can you show these tables so we can take a look?
A new coat is $123 but you get 45% off. How much is the coat? Code: 100% | 1% | 45% | etc ... ---------------------------------------------------------$123 | $1.23 |$55.35 | whatever ...
/100     *45
I'm not sure how to apply this to trigonometry but we didn't bother and went with algebra.
I would say "How do we get this over there by itself" and then she would recite a rule she had learned and then go through the motions. She had no concept of what algebra was about, but was able to memorize processes to solve "standard" problems.
Yes, exactly. Though maybe it's not the kids but these new systems ruining math for everyone. I also learnt that long division is now replaced by guessing.

#### SamR

Joined Mar 19, 2019
3,819
Was at the cashier, a teenage girl, after making a small purchase and gave her a $5 dollar bill for a$3.56 purchase. Her cash register wasn't working and she couldn't find a calculator to figure how much change to give me. So I told her it was $1.44. She ignored me and continued trying to work it out on paper and finally got her answer and startled looked up at me with big round eyes and said "How did you know that?" I didn't say it but in my mind, I said "I graduated 8th grade". #### MrAl Joined Jun 17, 2014 8,604 A few years ago my neighbor's daughter had failed business math on her second attempt and this was all she needed to graduate from her prestigious college in Bangkok . Her dad was ready to throw in the towel when I volunteered to see if I could help. The major part of was differential calculus which, the principles of which she seemed to grasp, but algebra...that was very frustrating for me. I would say "How do we get this over there by itself" and then she would recite a rule she had learned and then go through the motions. She had no concept of what algebra was about, but was able to memorize processes to solve "standard" problems. At one point she picked up her calculator when I said "Three plus 8, what is that?" Which was quickly followed with "No! You don't need a calculator for that!" When her dad told me that she passed the final exam I was completely stunned. Kids today, huh? So we see why designs can be so poor and where this world is heading. #### MrAl Joined Jun 17, 2014 8,604 Was at the cashier, a teenage girl, after making a small purchase and gave her a$5 dollar bill for a $3.56 purchase. Her cash register wasn't working and she couldn't find a calculator to figure how much change to give me. So I told her it was$1.44. She ignored me and continued trying to work it out on paper and finally got her answer and startled looked up at me with big round eyes and said "How did you know that?" I didn't say it but in my mind, I said "I graduated 8th grade".
And her reply was, "I hear that grade is very hard to pass."

#### SamR

Joined Mar 19, 2019
3,819
Similarly... A guy I know left the grocery store and in the parking lot encountered a young lady standing beside her car distraught and nearly in tears. He asked her what was wrong and she told him "I can't unlock my car door, I keep pushing the button and it doesn't do anything. The battery must be dead." He said "Here, let me try" and asked her for the keyring in her hand. When she gave it to him he found the car key and unlocked and opened the door for her and gave her keys back. She looked at the keys and then looked at him utterly gobstruck and speechless.

#### ci139

Joined Jul 11, 2016
1,696
A new coat is \$123 but you get 45% off. How much is the coat?
$$Cost_{FINAL}=\left({1-0.45}\right)·\123=0.55·\123=\frac{\left({1+0.1}\right)·\123}2=\frac{\123+\12.3}2=\frac{\135.3}2=\67.65$$
? why tables

#### upand_at_them

Joined May 15, 2010
766
How exactly it is that you can get from a = b / c to c = b / a is not taught. Apparently this method is taught internationally. This is all fine if you choose hospitality or psychology later on but not if you're actually going to need math later on, I would think.
I disagree. I don't think it's ever fine. I've heard plenty of people argue that "I learned algebra but I never use it". But that isn't the point of algebra. Learning advanced ideas are what develop the mind. Sure, it lays the groundwork for further advanced math, but it's also about *using your brain*. We need a well-developed mind so that we can make sense of the world around us and make informed and intelligent decisions.

#### lindula

Joined Sep 23, 2016
82
Kids like mine (the ones that actually understand math and science) will rule the world. I'm not worried.
Not likely, most of our presidents were C students.