USA Is #2

[f1b]

I make folks go look up the answers for themselves so they actually learn something."
Your nucking futz, it is the exact same order. You have missed the whole point, the way I teach, which is obvious you are not here much, I make folks go look up the answers for themselves so they actually learn something.. MDAS led Foo1bar to exactly where I wanted him to go PEMDAS.

Yes, that's where I went, and if you read it you can see that the author has a real valid point - the same one that CA_Tom made.
The mnemonic is misleading - normally mnemonics have each letter be a step in the sequence. ex. "Every good boy deserves fudge" or BBROYGBVGW, or "king paul came over for good sex very fine indeed"

But in this mnemonic it is NOT the case.
That makes it a bad mnemonic.

There is a significant difference between
1> Multiplication
2> Division
3> Addition
4> Subtraction

and

1> Multiplication AND division
2> Addition AND subtraction

They are NOT the same order.

Let's use each of these possible order of operation rules to evaluate

32 / 2 * 8

Under the first set we do all the multiplication first, and then do division.
2 * 8 = 16
32 / 16 = 2
therefore
32 / 2 *8 = 2

Under the second set (the one that is the generally agreed upon "correct" order of operations but is not what you'd expect from the "My Dear Aunt Sally" mnemonic)
we would do:
32 / 2 = 16
16 * 8 = 128
therefore
32 /2 *8 = 128

So under one set of rules, you get 2 and under the other you get 128.
I think this demonstrates that contrary to your assertion, they are not the "exact same" order.

"I make folks go look up the answers for themselves so they actually learn something."
So what were you trying to make me and others learn?
That you learned a bad mnemonic when you were a kid? Or that there exists this bad mnemonic that isn't being used much? Or that you value someone learning a bad mnemonic more than them actually learning the actual information?

[Sunking]

1> Multiplication AND division
2> Addition AND subtraction

They are NOT the same order.

Yes they are the exact same order, you and CA are leaving out Left to Right which applied to MDAS. PEMDAS (Please Excuse My Dear Aunt Sally) went one step further to include parentheses or other grouping is done first, exponents second. followed MDAS.

MDAS was a mnemonic for students to remember basic order of operations. As part of that lesson, teachers did explain the order was Multiplication and Division (L>R) , then Addition and Subtraction (L>R). Additionally they taught that parentheses and exponents were always performed before MDAS. It was later changed to Please Excuse My Dear Aunt Sally to include parentheses and exponents. But some bone headed students took it to heart of literal order. The final version became what is below and bullet proof for slow students who fail to listen.




My whole point and intent was to get you to the Blue Box above which was born with MDAS that I was originally taught. That is why I said younger folks would not know what MDAS was because it is not used anymore because of the confusion it caused in some students.

[f1b]

Yes they are the exact same order, you and CA are leaving out Left to Right

No.
Left to right applies within a given level.
We are pointing out that "MDAS" implies DIFFERENT LEVELS for multiplication vs. division.

Here's another example that hopefully will make it more clear why MDAS is wrong.

The equation:
x = 4 * 4 / 2 * 2 * 2

Evaluating with MDAS op precedence
4 * 4 = 16
so:
x =16 / 2 * 2 * 2

2 * 2 = 4
so:
x = 16 / 4 * 2

4 * 2 = 8
so:
x = 16 / 8

Now for division:
16 / 8 = 2
x = 2

The correct way would be:
4* 4 = 16; x=16/2 *2*2
16/2 = 8; x = 8*2*2
8*2=16 ; x=16*2
16*2=32; x=32

[Living Large]

A mnemonic is just a tool. When a tool is not used right, the results are not as desired. A pipe wrench is fantastic, unless you try using it backwards - it just slips. Saying MDAS as a tool is "bad" is a subjective and IMO incorrect assessment. It is perfectly functional if students are taught how to use it, which includes a lot more than the letters MDAS. Personally, I didn't need MDAS to learn OOO - it came naturally.

[Sunking]

No.
Left to right applies within a given level.
We are pointing out that "MDAS" implies DIFFERENT LEVELS for multiplication vs. division.

OK I see what you and the others are trying to say. My Bad. The whole exercise was to get people to go look it up. After doing it for some 40+ years it becomes automatic

[azdave]

Apparently reading is not your strong point. So here it is again in LARGER PRINT for you and I am typing slowly so you understand.

So it's okay to belittle those we're trying to teach? Is that like tough love?