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Solve this simple math problem: 48/2(9+3)
- Thread starter coolwater
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Same brand scientific calculator, two different answers.
What mode are they in? From a quick search:
If you choose to use a calculator to solve the math problem, your calculator must be in scientific notation. Only a calculator in scientific notation will follow PEMDAS and the order of operations. A non-scientific calculator will yield an incorrect answer.
i worked it out as 288 using BODMAS order, or PEDMAS as you americans call it
good idea to use Wolfram, that thing is pretty insane, and even Google can do it! step it up OS X calculator!
EDIT:
oh! looks like you just need to add an asterisk
good idea to use Wolfram, that thing is pretty insane, and even Google can do it! step it up OS X calculator!
EDIT:
oh! looks like you just need to add an asterisk
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The lack of proper notation makes the equation ambiguous. 100% of Elementary School teachers should agree.
No it doesn't. It is perfectly noted and not ambiguous at all. Feel free to ask any teacher, what do you think is missing from the equation? Btw, what are basing your 100% figure on? Have u asked even one?
also with problems like this you can work out how large the answer might be before calculating, 48/2 is a double digit number and multiplying that by a number wont give 2
(48/2)(9+3) would be straight forward. The way the formula was originally typed lends interpretation as:
48/
2(9+3)
Why would someone choose to group one set with parentheses and not another unless they were being intentionally ambiguous?
Did you call your elementary school teacher? I didn't. They taught me well enough the first time.
Because to teach kids the correct way to do math, teachers make up examples in which some actual thinking is needed to solve the problem. Written the way you just put it, it does not teach pemdas, something this math problem is obviously supposed to do. Your math teacher obviously taught u wrong or you just forgot how to do math as my numerous facts supported by searches prove. I dont need to call anyone, I taught SAT review courses for over a decade and my wife is currently a math teacher. But please take my challenge. Go to your local school and ask any math teacher how to properly do pemdas if u still can't accept the fact that u are clearly, beyond any shadow of a doubt, wrong.
BS. The only lesson to be learned here is that teachers devise lame pneumonic devices to confuse kids. If you're so damn smart, why wouldn't you properly write the correct equation with proper groupings in the first place?
Look at the poll, the groups divided about 50/50. Great job you and your teaching pals did. So much for "perfectly noted." This example is a classic glass half full/empty exercise.
Tastes great. (who's with me)
Given your argument I would have thought you'd represent "less filling".Tastes great. (who's with me)
B
@ Mac'nCheese and Tilpots
I think tilpots has shown that he understands the proper priority of operation but is simply stating the fact the this notation can lead to interpretation or at least doubt as to what is meant. I clearly see the answer as 288 and would consider 2 a wrong answer. But if you take it for it's face value, it has to be 288, write it down with ÷ and X, instead, you'll end up with 288, and that's what should be meant. But I still think this is a ****** notation and a second set of parentheses would make it clear.
Wow I should be studying way more complex stuff than this right now...
I think tilpots has shown that he understands the proper priority of operation but is simply stating the fact the this notation can lead to interpretation or at least doubt as to what is meant. I clearly see the answer as 288 and would consider 2 a wrong answer. But if you take it for it's face value, it has to be 288, write it down with ÷ and X, instead, you'll end up with 288, and that's what should be meant. But I still think this is a ****** notation and a second set of parentheses would make it clear.
Wow I should be studying way more complex stuff than this right now...
MacnCheese is correct
PEMDAS is more like this. PEMDAS isn't really an accurate name, but it helps remember the basic order.
1) Parenthesis
2) Exponents
3) Multiplication or division ... going from left to right
4) addition or subtraction ... going from left to right.
48/2(9+3)
=48/2(12) or 48/2 * 12
(by parenthesis)
No exponents
No addition or subtraction
=24(12)
(by multiplication or division from left to right)
=288
(by multiplication or division from left to right ... again)
288 is the answer. There is no way you can get 2 by following the order of operations.
And people should know better than putting a whole equation into a calculator and depending on that answer ... (spotlight, google, calculator)
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BS. The only lesson to be learned here is that teachers devise lame pneumonic devices to confuse kids. If you're so damn smart, why wouldn't you properly write the correct equation with proper groupings in the first place?
Look at the poll, the groups divided about 50/50. Great job you and your teaching pals did. So much for "perfectly noted." This example is a classic glass half full/empty exercise.
Tastes great. (who's with me)
I explained why it might be written the way it is, you choose to ignore that like you ignored all the other facts here. The group is divided because some people just don't learn, we have posted exactly why pemdas gives the correct answer when used properly but stubborn people here still say things like well... It's half full/half empty. No, it's not. It's black and white and if you can't see that by now, you never will. Some people just can never admit to mistakes and will never learn anything. Don't blame the teachers...
Oh, I can admit when I'm wrong. I used to believe in protecting tenure for teachers. See?
Then we can end this on agreement. I don't believe in it too. My wife should keep her job if and only if she continues to do it well not because its near impossible to fire tenured staff. But don't think I missed your sarcasm...
They know math, just not the order of operations. Or they are putting the whole equation into a scientific calculator, Google, or spotlight. If they did the problems in a calculator, google or spotlight with the correct order of operations, then theyd get the correct answer.
So people can learn how to do math properly. If teachers quized students with the "easy" version of questions, they would never really learn anything but the basics. The harder something is to do, the more you learn how to reason, how to think, how to work through problems and solve them. It's like asking why kids learn more and more vocabulary words when, in the end, they probably will just use the most common ones.
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