Okay Math Geniusues... What's 48÷2(9+3) ?

[Nancy1999]

Originally Posted by AMD

Is this a test? LOL

48÷2(9+3)
= 48/2(12)
= 48/24
= 2

Great explanation, and because work in parenthesis goes first, it must be completed this way. Another way to look at it would be:

_48_
2(12)

Next

_48_
24

The underline stands for divide. So I'm with the two's.

[Ellie May]

Originally Posted by OwnedByJezebel

The difference in answers here is due to when some believe the "parentheses goes away."

I don't happen to believe that just because you add the 9 and the 3, the parentheses has gone away. After you add the 9 and the three, the equation becomes:

48 / 2(12)

Adding two numbers in a parentheses does not eliminate the parentheses. Taking what is in the parentheses and multiplying it to the number just to the left (or unknown, such as "x", "y", etc.) does eliminate the parentheses.

Exactly. The () haven't been eliminated yet. And when there are (), they have to be done first. That 2 has to be multiplied by what's in the () to clear them.

[megantheswimmer]

288.

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

[Bitsy]

Originally Posted by AMD

Essentially the problem is 48/[2(9+3)]. You cannot split up the demoninator...solve the entire denominator before dividing. It's alot easier to see written as a fraction numerator on top of a demoninator instead of the "/" symbol.

To get 288 as the correct answer, the problem would have to be written (48/2)*(9+3). Otherwise you cannot divide before solving your denominator.

I haven't read all the responses....but this is what I think also. Just didn't know how to put it into words.

To be clear....my answer is 2

[107barney]

Setting the problem = x still gives me 288 when I solve for x.

48÷2(9+3) = x
x/48=1/2(9+3)
x/48=1/2*12
x/48=6
x=6*48
x=288

[Bitsy]

Just thought of another way of saying it that might help....
My daughter is in 3rd grader and sometimes they have problems where they have to write math out in words.

So, try saying it:
Forty-eight divided by two times nine plus three.

You have to find out what you are dividing 48 by. The key is finding out your denominator.
2 times 9+3 equals 24

Now your problem would read:
48 divided by 24.

Don't know if that helps or not!

[fasteddie]

I think I'm still sticking with 2 as MY answer. To think, this may be my most popular thread ever on YT...

[MaddiesMommie]

I actually teach this skill in 5th grade. YES, PEMDAS is used ANY time you have multiple operations however, what most people forget is even though multiplication and division are at the same level and the left to right rule applies, parentheses () outrank division.

This problem is written with the 2 with the parentheses, therefore, the 2 must stay with them until it is complete. This indicates that the values must be multiplied before doing any other operation.

48÷2(9+3) is different than 48÷2X(9+3)
this answer =2 this answer is =288
The 2 beside the ()
means you must X
2 by the answer inside
to be finished.

Now, thanks for making me work on my last day of spring break.

[MaddiesMommie]

Here is another example I found to look at if it helps...
(4 / 2) + 4(5 - 2)^2
= (2) + 4(3)^2
= 2 + 4(9)
= 2 + 36
= 38


^2 is exponent

[107barney]

Originally Posted by fasteddie

I think I'm still sticking with 2 as MY answer. To think, this may be my most popular thread ever on YT...

I think the problem should be rephrase so that Teddy can solve it for me

48s÷(9s+:a imeeyork) =
288 s when Teddy Bumpkins Solves for

ETA: I can't get even get the # of yorkies right. Geez.

[MaddiesMommie]

Originally Posted by 107barney

I think the problem should be rephrase so that Teddy can solve it for me

48s÷(9s+:a imeeyork) =
288 s when Teddy Bumpkins Solves for

ETA: I can't get even get the # of yorkies right. Geez.

I agree with Teddy!

[Bitsy]

Another thing that might help....

Just now read some of the responses and I see that the () causes confusion.

Someone said you can replace the () with * after you solve it. But, that is incorrect. The () were used to tell you to do that part first.

48/ 2(9+3)

You have to solve the () first and then complete the denominator. The denominator includes the () which means you have to completely solve it before you move on.

[megansmomma]

Originally Posted by 107barney

I think the problem should be rephrase so that Teddy can solve it for me

48s÷(9s+:a imeeyork) =
288 s when Teddy Bumpkins Solves for

ETA: I can't get even get the # of yorkies right. Geez.

Good answer! Teddy RULES!

[Bitsy]

Originally Posted by MaddiesMommie

I actually teach this skill in 5th grade. YES, PEMDAS is used ANY time you have multiple operations however, what most people forget is even though multiplication and division are at the same level and the left to right rule applies, parentheses () outrank division.

This problem is written with the 2 with the parentheses, therefore, the 2 must stay with them until it is complete. This indicates that the values must be multiplied before doing any other operation.

48÷2(9+3) is different than 48÷2X(9+3)
this answer =2 this answer is =288
The 2 beside the ()
means you must X
2 by the answer inside
to be finished.

Now, thanks for making me work on my last day of spring break.

Yes...that is exactly what I was trying to say! Thanks Teach!

[Rhetts_mama]

I love that a math problem has 6 pages (and counting) of responses to it!