Debate: 48 ÷ 2(9+3) = ?
- Thread starter davidjl123
- Start date
Eyup
EDIT: I also used the parenthesis ordering mentioned around one minute in the video I just embedded, and I got 288. The way he showed followed that multiplication and division are grouped first, and then addition (excluding subtraction because subtraction is really just the addition of a negative). So like this:
((48/2)(9+3)) = ?
Honestly, I love math. Why must you guys dislike it so much? :<
And one thing's for sure, wasn't I proven wrong with how to go about this process... But, not completely.
Duffie's Learning Time!
You see, what most people would do is distribute, right away. 2(9 + 3) would end up being 24. That's what the calculator would say, that's what the numbers would say. Right after that, just do 48 / 24, and you get 2. Simple as that.
But, if you look more closely, it is obviously wrong.
The correct way to do this is still under PEMDAS, more or less; just not in the way you originally learned it, I suppose.
Yes, you do the parenthesis first, being (9 + 3), resulting in a solid 12. With that, you now have the equation 48 / 2 x 12. From then on, you complete the equation from left to right. 48 / 2 is 24, then 24 x 12 results in the answer being 288.
As the video above says, PEMDAS is morally wrong, but only to a certain justification to make things less confusing.
Also, PEMDAS means Parenthesis(), Exponents², Multiplication*, Division÷, Addition+, and Subtraction-. You can put Brackets[] with parenthesis, of course.
Duffie's Learn Time End
... And now that I look at it, I think I know why I got it wrong at first. The reason I'm so used to distributing first is the fact I usually see parenthesis when x is a factor in the equation, usually resulting in something like... 5(x + 2). From this, you would end up getting 5x + 10, considering you can't add x and 10 together, moving on from parenthesis to multiplication in PEMDAS.
Well, you know what they say, you learn something new everyday! (Hey, that rhymed!)
Thanks for that, davidjl123. I love you for bringing math here. <3
And one thing's for sure, wasn't I proven wrong with how to go about this process... But, not completely.
Duffie's Learning Time!
You see, what most people would do is distribute, right away. 2(9 + 3) would end up being 24. That's what the calculator would say, that's what the numbers would say. Right after that, just do 48 / 24, and you get 2. Simple as that.
But, if you look more closely, it is obviously wrong.
The correct way to do this is still under PEMDAS, more or less; just not in the way you originally learned it, I suppose.
Yes, you do the parenthesis first, being (9 + 3), resulting in a solid 12. With that, you now have the equation 48 / 2 x 12. From then on, you complete the equation from left to right. 48 / 2 is 24, then 24 x 12 results in the answer being 288.
As the video above says, PEMDAS is morally wrong, but only to a certain justification to make things less confusing.
Also, PEMDAS means Parenthesis(), Exponents², Multiplication*, Division÷, Addition+, and Subtraction-. You can put Brackets[] with parenthesis, of course.
Duffie's Learn Time End
... And now that I look at it, I think I know why I got it wrong at first. The reason I'm so used to distributing first is the fact I usually see parenthesis when x is a factor in the equation, usually resulting in something like... 5(x + 2). From this, you would end up getting 5x + 10, considering you can't add x and 10 together, moving on from parenthesis to multiplication in PEMDAS.
Well, you know what they say, you learn something new everyday! (Hey, that rhymed!)
Thanks for that, davidjl123. I love you for bringing math here. <3
cooliorules
That Awkward Noodle
BIMDAS (That's what us Aussie's call it)
Bracets
Indicies
Multiplication
Division
Addision
Subtraction
48 ÷ 2(9+3)
Do the brackets, 9+3=12
So then it's 48÷2x12
Then you do it in the order from left to right.
48÷2=24
24x12=288
Bracets
Indicies
Multiplication
Division
Addision
Subtraction
48 ÷ 2(9+3)
Do the brackets, 9+3=12
So then it's 48÷2x12
Then you do it in the order from left to right.
48÷2=24
24x12=288
Thank you! Why people are rating this thread negatively/acting sarcastic is beyond me.
48 ÷ 2(9+3)
48 ÷ 18+6
48 ÷ 24
24x2=48
x = 2
you can also skip the 18+6 by adding 9 and 3 then multiplying by 2, therefore no distribution.
I see what you mean with the multiplication and division stuff though, so you are probably right.
48 ÷ 18+6
48 ÷ 24
24x2=48
x = 2
you can also skip the 18+6 by adding 9 and 3 then multiplying by 2, therefore no distribution.
I see what you mean with the multiplication and division stuff though, so you are probably right.
It's because there's something about problems like that that are easily overlooked, causing people to get a completely different answer from the one they wanted. (As far as I can tell)
Duffie I know those feels, especially during those years of learning Algebra I & II.
And thank you for further explaining.
Yep, it's 288 for me. P in PEMDAS is Parenthesis (which is similar to brackets). Pretty much the people above has explained why it is the answer 
If the correct answer was 2, it should have been written like this: 48 / (2(9+3)).
If the correct answer was 2, it should have been written like this: 48 / (2(9+3)).
The answer is actually 288, as Duffie said you apply, PEMDAS.
STEP BY STEP MATH DONE BY ME WITH PICTURES:
MATH EXPLAINED:
Parethesis ( )
Exponents x^2
Multiplication (From left to right) *
Division (Left to right) /
Addition(Left to right) +
Subtraction (Left to right) -
**Left to right basically means what comes first in the equation you solve first (ex. 4/2*2 You would solve 4/2 first!))**
Hope this helped! c:
STEP BY STEP MATH DONE BY ME WITH PICTURES:
MATH EXPLAINED:
- You would need to apply (B)PEMDAS which stands for...
Parethesis ( )
Exponents x^2
Multiplication (From left to right) *
Division (Left to right) /
Addition(Left to right) +
Subtraction (Left to right) -
**Left to right basically means what comes first in the equation you solve first (ex. 4/2*2 You would solve 4/2 first!))**
- Solve what's in the parenthesis (9+3)
- Do the DIVISION NEXT 48/2(Read why above)
- Then you do the MULTIPLICATION 24*12
- Which equals 288
Hope this helped! c:
D
Deleted member 4601
Guest
48÷2(9+3)
=48÷2(12)
=48÷24
=2
48÷2(9+3)
=48÷(18+6)
=48÷24
=2
48÷2(9+3)
=48÷2(12)
=2(24)÷2(12)
=24÷12
=2
48÷2(9+3)
=48÷2(12)
=48x[2(12)]^(1/2)
=48x[1/2(12)]
=48x(1/24)
=48/24
=2
HOW ON EARTH DO YOU GET 288
I was educated that when something is expressed as a(x+y), it is equivalent to (ax+ay), with the parenthesis. Therefore in this case, in the second step, 2(12) should be done first due the the brackets.
=48÷2(12)
=48÷24
=2
48÷2(9+3)
=48÷(18+6)
=48÷24
=2
48÷2(9+3)
=48÷2(12)
=2(24)÷2(12)
=24÷12
=2
48÷2(9+3)
=48÷2(12)
=48x[2(12)]^(1/2)
=48x[1/2(12)]
=48x(1/24)
=48/24
=2
HOW ON EARTH DO YOU GET 288
I was educated that when something is expressed as a(x+y), it is equivalent to (ax+ay), with the parenthesis. Therefore in this case, in the second step, 2(12) should be done first due the the brackets.
That only applies when using variables, such as x or y!
When you see something, like 2(9+3), you can distribute ( Being what you've been doing there, multiplying the number next to the () into the (). ). But, it's best not to do that when it's like this.
Let me explain. When do you normally distribute? When using variables, such as x or y.
When you see an equation, like 2(x+3), you have to distribute, as you can't add together the x and the 3.
But, as you've done, you can add what's in the ().
Now, think about this; when you added those two numbers together, you formed one number. Now you can take that number out of the (). What does it look like now..?
48 / 2 * 12
tl;dr - Do what you do inside the (), take it out of the () and add it to the equation, since it's just one number.
2 is not enclosed in the parenthesis/brackets. You distribute 2 to x and y because they can't be combined. But if it were to be 2 (x+x) then it would be 2 (2x) aka 2 x 2x, then you proceed to do the problem left to right.