48÷2(9+3) = ?

[CurlyBill]

Order of operations... the answer is 2.

[CAluvdubya]

psst..how did you make the division sign/ I can’t figure out how on my keyboard...Thanks

[Dust in the Wind]

Did not remember what the signs were named but you are correct as I remember math before computors. This must be partly an age driven discussion. LOL

[SoothingDave]

http://en.wikibooks.org/wiki/Algebra/Order_of_Operations

Are you following some other set of rules.

[SeaHawkFan]

Here is a YouTube video that should eliminate all the excuses of the 288ers.

http://www.youtube.com/watch?v=yiQ_q0oXVdU

[DollyCali]

BTTT

[meyer]

Actually, the problem itself is elementary, but the interpretation of the equation has presented a significant cause for argument. I was originally adament about what I saw as a simple math problem, even applying the distributive property to what appeared to be the complete denominator. It wasn't until I was convinced that everything to the right of the division sign was NOT necessarily the denominator that I saw that 288 could be considered the obvious answer, just as I had seen 2 to be.

In the future, I will "parenthesize" in a manner that makes it obvious as to which order is to be followed.

[CharacterCounts]

Okay, I was reading the / as a fraction. However, I decided to re-evaluate the expression in a different manner. I changed the division by 2 to multiplication by .5

thus the expression would read:

48 * .5 * (9+3) = 288.

I stand corrected but think the expression is poorly written.

[jwalsh07]

I'm about 5 months shy of 60 Meyer. But I tutor my grandkids in Math because their math teachers suck and as luck would have it we just covered orders of operations. :-}

I'm also an engineer who used the TI-85 nearly 20 years ago so I know how the orders work in that calculator which is not consistent with almost all programming languages and newer generation calculators most of which listen to Auntie BEDMAS.

Here's to old guys!

[grateful]

This is not an algebraic equation. An algebraic equation would include at least one variable. There is not a variable in sight. Thus, the distributive property of multiplication will not be used and order of operations would be followed.

Thus... 48/2(9+3) = 48/2*(9+3)

By order of operations...

48/2*(12)
24*12 = 288

[ThomasThomas]

Also, note that the original expression did not use a "/", but a "÷"

The picture of the calculators is different than the typed text in the post. The original expression on the calculators did use a "/" and the note used a "÷"

[RBranha]

“Here is a YouTube video that should eliminate all the excuses of the 288ers.”

Show us how to distribute

(24)(9+3)

then show us

(48÷2)(9+3)

[ctdonath2]

“Could make a difference if you’re trying to say, land a Mars rover.”

What did make the difference was feet vs meters.
Those units got confused between two software modules for a Mars lander, which decided it was on the ground so it shut off its retrorocket. Problem was, because the wrong units were used, it was still two miles up.
Splat.

[Forty-Niner]

“If 2(9 + 3) is not the same as 2 * (9 + 3), then what is the difference? Please cite a source.

I get “9 plus 3 equals 12 times 2 equals 24” for both.

What is this magical new arithmetic operation, if it is not multiplication?”

Standing alone you are correct, but in the context of the subject formula it leads to a gross miscalculation.

As stated the originaly stated the formula does not include the * sign, by adding it the solution leads one to miscalculate the answer as 288.

[CAluvdubya]

I'm following the same ones you are. We have been saying the same thing...288 is the answer. Order of Operations I'm following are the same as your link.

Parenthesis first, multiplication and division second. Adding and subtracting third. In case of two operations of equal value, such as multiplication and division, work the problem from left to right.

[Melas]

The answer is 2 It would make more sense if it looked like this:

.

48

___

2(9+3)

[Melas]

No, expressed correctly as an improper fraction the result is easier to discern. Any time the order of operations seems confusing, look at the expression as a fraction and remember that the numerator and denominator are resolved independently.

[ctdonath2]

The answer depends on the specified order and precedence of operations, which can vary depending on implementation. For some systems it is defined as multiplication being evaluated before division, for others it is equal precedence evaluated left to right. Hence the two different answers: both 2 and 288 are correct depending on how the ambiguity is implemented.

This is one of the first issues I have to teach my beginning programming students, and why I recommend generous use of parentheses. The answer depends on implementation.

[SoothingDave]

As stated the originaly stated the formula does not include the * sign, by adding it the solution leads one to miscalculate the answer as 288.

What is the operation when there is no explicit multiplication sign used? What is it called? Where does it fit in on the order of operations and why isn't it mentioned anywhere?

[RBranha]

“As stated the originaly stated the formula does not include the * sign, by adding it the solution leads one to miscalculate the answer as 288.”

The * is not included but is implied. Whether or not the * is included, the multiplication operation is done the same way in both cases.

2*(9+3) = 2(9+3)

48/2(9+3) = 48/2*(9+3)