Posted on 04/12/2011 1:32:09 PM PDT by grundle
Texas Instruments TI-85 says:
48÷2(9+3) = 2
But Texas Instruments TI-86 says:
48÷2(9+3) = 288
The correct answer, with standard mathematical notation, is 2. The other answer occurs by dividing 48 by 2, yielding 24, and then multiplying THAT by 12. Bad notation!
I understand, but the mnemonic doesn’t include the grouping of multiplication and division, as well as addition and subtraction. I do a lot of computer math, and have had to deal with order of operations quite a bit.
Searching for “order of operations” or “mathematical precedence” will confirm my opinion.
lol, I used that in-game (WoW) a couple of days ago ;)
Bikk
Of course...They are inverse operations and consequently get the same precedence.
and to think that I had to learn this stuff BEFORE Calculators.. well..there were calculators..but they could not answer this question and cost $300.
Although we WERE allowed to use ...SLIDE RULES ... (runs for cover)
But there IS NO PARENTHESIS before the 2. You’re implying it. So the operation is to do the math outside any parenthesis first. Thus the answer is 288.
wouldn’t that make your answer (total) 6? ;)
Oh no, wait....that's the meaning of life.
Never mind.
That’s the math I was taught.
Maybe that’s how we get the budgets we have these days.
Add 14 trillion to the deficit, subtract 8 billion = OMG! EXTREME BUDGET CUTS! WOMEN AND MINORITIES HIT HARDEST! LEADING ECONOMISTS BLAME BUSH.
48 ÷ 2 * (9+3)
= 48 / 2 * 12
= 24 * 12
= 288
Operator precedence is left to right and parens first.
Thank you.. that’s the way I see it (and learned it) :)
Bikk
48 ÷ 2 * (9+3)
= 48 / 2 * 12
= 24 * 12
= 288
Operator precedence is left to right and parens first.
Excel says 288.
I was post-slide rule but pre-affordable programmable calculator. I also do a lot of computer programming.
Parenthesis are our friends! LOL
Does gray hair cause memory loss, or is it the other way around?
IT doesn’t use RPN it uses PN HP uses RPN.
But like the sentence about you must know the rules you are using for it to make since.
I’m no math major, but I did stay at a Holiday Inn Express last night. The TI-85 has it wrong (which explains why it was replaced by the TI-86).
Perl says 100100000.
Man, do we know how to solve problems.
KFTC
I like this answer because to my intuition I multiplied the 2(9+3) first and I don’t think I would have done that if it had been written 2 * (9+3). 2(9+3) makes it obvious the whole thing has to be done in that way and the answer is 2.
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