48

[insomniac]

= 48/2(9+3)
= 48/18+6
= 48/18 + 48/6 [48/18+6 becomes 2 fractions to be added]
= 48/18 + 48/18 [then. it's just a simple matter of finding the LCD, which is 18 and adding the 2 numerators; 48+48=96]
= 96/18
= 5.33

That's just all kinds of wrong, especially the bolded part.

[Patrick Chewing]

23 pages of this shit

[insomniac]

Who wrote this?

Not sure. My sister sent it to me, but it is basically what I said earlier.

[shlver]

23 pages of this shit

It is not shit. Without these kind of debates, standard notation would not have arisen. In the time of early mathematical texts, mathematicians would write introductions explaining their notation ridding any kind of interpretation and confusion.

[Rockets(T-mac)]

That's just all kinds of wrong, especially the bolded part.

Yea lol. You can't do that kind of expansion unless the addition occurs in the numerator. You just simply add 18 and 6 before you do anything else.

[Harion]

That's just all kinds of wrong, especially the bolded part.

heh. you caught the unedited version. i was writing that when i realized my error and had to recompute

[crosso√er]

So in conclusion, there is a huge inconsistency in educational curriculum.
For instance, I was taught that division takes precedence over multiplication; shiver says the complete opposite.

Some people think multiplication and division are interchangeable; and addition and subtraction are interchangeable. In reality (the way I was taught); division comes 1st, followed by multiplication, then division and then addition. Order of operations framework is based on that methodology. It's what I was taught when I live in Europe, and I have never in my life gotten a question (irregardless of complexity) incorrect using that method.

48 / 2 (9 + 3)
or
(65-15) / 5 - 7 -6 +6 x 10

Use my method

48 / 2 (12)
24 (12)
288

(50) / 5 - 7 - 6 + 6 x 10
10 - 7 - 6 + 6 x 10
10 - 7 - 6 + 60
-3 + 60
57

Notice my approach:

brackets first; followed by division, then multiplication, then subtraction and then addition.

Place this equation into any calculator that way and you'll get the same answer.

[Hyperephania]

After a bit further research it seems that there actually isn't one correct answer, but even according to this, 288 seems the more likely choice:


http://mathforum.org/library/drmath/view/54341.html

Some texts make a rule, as in your second solution, that
multiplication without a symbol ("implied multiplication") should be
done before any other operations in an expression, including "explicit
multiplication" using a symbol. Following this rule, you would
multiply a by x, then multiply b and y, then divide one by the other.
Some (probably most) texts don't mention such a rule - but some of
those may use it without saying so, which is far worse.

I don't know of a general rule among mathematicians that implied
multiplication should be done before explicit multiplication. As far
as I'm concerned, all multiplications fit in the same place in the
order of operations. It's not an unreasonable rule, though, since it
does seem that implied multiplication ties the operands together more
tightly, at least visually; but the idea of Order of Operations (or
precedence, as it is called in the computer world) is supposed to be
to ensure that everyone will interpret an otherwise ambiguous
expression the same way - so if some texts change the rules, or if
people do what feels natural, the purpose has been lost.

http://mathforum.org/library/drmath/view/54341.html

[QUOTE]The problem is that some calculators that allow multiplications to
be implied as in the former case treat that as a higher precedence
operation (as some algebra texts say), while others treat all
multiplications alike (as most texts do, in my experience). You can
read a little about that here:

Order of Operations
http://mathforum.org/library/drmath/view/54341.html

That has a bad link to TI's site; a current version can be found by
going to their Knowledge Base and searching for "implied
multiplication". Here is a quote:

Solution 11773: Implied Multiplication Versus Explicit
Multiplication on TI Graphing Calculators.

Does implied multiplication and explicit multiplication have the
same precedence on TI graphing calculators?

[B] Implied multiplication has a higher priority than explicit
multiplication to allow users to enter expressions, in the same
manner as they would be written. For example, the TI-80, TI-81,
TI-82, and TI-85 evaluate 1/2X as 1/(2*X), while other products
may evaluate the same expression as 1/2*X from left to right.
Without this feature, it would be necessary to group 2X in
parentheses, something that is typically not done when writing
the expression on paper.

This order of precedence was changed for the TI-83 family, TI-84
Plus family, TI-89 family, TI-92 Plus, Voyage

[sixerfan82]

24 pages and there are people who still think the answer is 288?

Really?

[Semi]

where is your reasonable conclusion it's not 288 when you're talking shit?